New upstream version 1.2.3

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This is quagga.info, produced by makeinfo version 6.3 from quagga.texi.

Copyright (C) 1999-2005 Kunihiro Ishiguro, et al.

     Permission is granted to make and distribute verbatim copies of
     this manual provided the copyright notice and this permission
     notice are preserved on all copies.

     Permission is granted to copy and distribute modified versions of
     this manual under the conditions for verbatim copying, provided
     that the entire resulting derived work is distributed under the
     terms of a permission notice identical to this one.

     Permission is granted to copy and distribute translations of this
     manual into another language, under the above conditions for
     modified versions, except that this permission notice may be stated
     in a translation approved by Kunihiro Ishiguro.
INFO-DIR-SECTION Routing Software:
START-INFO-DIR-ENTRY
* Quagga: (quagga).             The Quagga Software Routing Suite
END-INFO-DIR-ENTRY

   This file documents the Quagga Software Routing Suite which manages
common TCP/IP routing protocols.

   This is Edition 1.2.3, last updated 4 February 2018 of 'The Quagga
Manual', for Quagga Version 1.2.3.

   Copyright (C) 1999-2005 Kunihiro Ishiguro, et al.

     Permission is granted to make and distribute verbatim copies of
     this manual provided the copyright notice and this permission
     notice are preserved on all copies.

     Permission is granted to copy and distribute modified versions of
     this manual under the conditions for verbatim copying, provided
     that the entire resulting derived work is distributed under the
     terms of a permission notice identical to this one.

     Permission is granted to copy and distribute translations of this
     manual into another language, under the above conditions for
     modified versions, except that this permission notice may be stated
     in a translation approved by Kunihiro Ishiguro.

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Quagga
******

Quagga is an advanced routing software package that provides a suite of
TCP/IP based routing protocols.  This is the Manual for Quagga 1.2.3.
Quagga is a fork of GNU Zebra.

   Copyright (C) 1999-2005 Kunihiro Ishiguro, et al.

     Permission is granted to make and distribute verbatim copies of
     this manual provided the copyright notice and this permission
     notice are preserved on all copies.

     Permission is granted to copy and distribute modified versions of
     this manual under the conditions for verbatim copying, provided
     that the entire resulting derived work is distributed under the
     terms of a permission notice identical to this one.

     Permission is granted to copy and distribute translations of this
     manual into another language, under the above conditions for
     modified versions, except that this permission notice may be stated
     in a translation approved by Kunihiro Ishiguro.

* Menu:

* Overview::
* Installation::
* Basic commands::
* Zebra::
* RIP::
* RIPng::
* OSPFv2::
* OSPFv3::
* ISIS::
* NHRP::
* BGP::
* Configuring Quagga as a Route Server::
* VTY shell::
* Filtering::
* Route Map::
* IPv6 Support::
* Kernel Interface::
* SNMP Support::
* Zebra Protocol::
* Packet Binary Dump Format::
* Command Index::
* VTY Key Index::
* Index::

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1 Overview
**********

Quagga is a routing software package that provides TCP/IP based routing
services with routing protocols support such as RIPv1, RIPv2, RIPng,
OSPFv2, OSPFv3, IS-IS, BGP-4, and BGP-4+ (*note Supported RFCs::).
Quagga also supports special BGP Route Reflector and Route Server
behavior.  In addition to traditional IPv4 routing protocols, Quagga
also supports IPv6 routing protocols.  With SNMP daemon which supports
SMUX and AgentX protocol, Quagga provides routing protocol MIBs (*note
SNMP Support::).

   Quagga uses an advanced software architecture to provide you with a
high quality, multi server routing engine.  Quagga has an interactive
user interface for each routing protocol and supports common client
commands.  Due to this design, you can add new protocol daemons to
Quagga easily.  You can use Quagga library as your program's client user
interface.

   Quagga is distributed under the GNU General Public License.

* Menu:

* About Quagga::                Basic information about Quagga
* System Architecture::         The Quagga system architecture
* Supported Platforms::         Supported platforms and future plans
* Supported RFCs::               Supported RFCs
* How to get Quagga::            
* Mailing List::                Mailing list information
* Bug Reports::                 Mail address for bug data

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File: quagga.info,  Node: About Quagga,  Next: System Architecture,  Up: Overview

1.1 About Quagga
================

Today, TCP/IP networks are covering all of the world.  The Internet has
been deployed in many countries, companies, and to the home.  When you
connect to the Internet your packet will pass many routers which have
TCP/IP routing functionality.

   A system with Quagga installed acts as a dedicated router.  With
Quagga, your machine exchanges routing information with other routers
using routing protocols.  Quagga uses this information to update the
kernel routing table so that the right data goes to the right place.
You can dynamically change the configuration and you may view routing
table information from the Quagga terminal interface.

   Adding to routing protocol support, Quagga can setup interface's
flags, interface's address, static routes and so on.  If you have a
small network, or a stub network, or xDSL connection, configuring the
Quagga routing software is very easy.  The only thing you have to do is
to set up the interfaces and put a few commands about static routes
and/or default routes.  If the network is rather large, or if the
network structure changes frequently, you will want to take advantage of
Quagga's dynamic routing protocol support for protocols such as RIP,
OSPF, IS-IS or BGP.

   Traditionally, UNIX based router configuration is done by 'ifconfig'
and 'route' commands.  Status of routing table is displayed by 'netstat'
utility.  Almost of these commands work only if the user has root
privileges.  Quagga has a different system administration method.  There
are two user modes in Quagga.  One is normal mode, the other is enable
mode.  Normal mode user can only view system status, enable mode user
can change system configuration.  This UNIX account independent feature
will be great help to the router administrator.

   Currently, Quagga supports common unicast routing protocols, that is
BGP, OSPF, RIP and IS-IS. Upcoming for MPLS support, an implementation
of LDP is currently being prepared for merging.  Implementations of BFD
and PIM-SSM (IPv4) also exist, but are not actively being worked on.

   The ultimate goal of the Quagga project is making a productive,
quality, free TCP/IP routing software package.

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File: quagga.info,  Node: System Architecture,  Next: Supported Platforms,  Prev: About Quagga,  Up: Overview

1.2 System Architecture
=======================

Traditional routing software is made as a one process program which
provides all of the routing protocol functionalities.  Quagga takes a
different approach.  It is made from a collection of several daemons
that work together to build the routing table.  There may be several
protocol-specific routing daemons and zebra the kernel routing manager.

   The 'ripd' daemon handles the RIP protocol, while 'ospfd' is a daemon
which supports OSPF version 2.  'bgpd' supports the BGP-4 protocol.  For
changing the kernel routing table and for redistribution of routes
between different routing protocols, there is a kernel routing table
manager 'zebra' daemon.  It is easy to add a new routing protocol
daemons to the entire routing system without affecting any other
software.  You need to run only the protocol daemon associated with
routing protocols in use.  Thus, user may run a specific daemon and send
routing reports to a central routing console.

   There is no need for these daemons to be running on the same machine.
You can even run several same protocol daemons on the same machine.
This architecture creates new possibilities for the routing system.

     +----+  +----+  +-----+  +-----+
     |bgpd|  |ripd|  |ospfd|  |zebra|
     +----+  +----+  +-----+  +-----+
                                 |
     +---------------------------|--+
     |                           v  |
     |  UNIX Kernel  routing table  |
     |                              |
     +------------------------------+

         Quagga System Architecture

   Multi-process architecture brings extensibility, modularity and
maintainability.  At the same time it also brings many configuration
files and terminal interfaces.  Each daemon has it's own configuration
file and terminal interface.  When you configure a static route, it must
be done in 'zebra' configuration file.  When you configure BGP network
it must be done in 'bgpd' configuration file.  This can be a very
annoying thing.  To resolve the problem, Quagga provides integrated user
interface shell called 'vtysh'.  'vtysh' connects to each daemon with
UNIX domain socket and then works as a proxy for user input.

   Quagga was planned to use multi-threaded mechanism when it runs with
a kernel that supports multi-threads.  But at the moment, the thread
library which comes with GNU/Linux or FreeBSD has some problems with
running reliable services such as routing software, so we don't use
threads at all.  Instead we use the 'select(2)' system call for
multiplexing the events.

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File: quagga.info,  Node: Supported Platforms,  Next: Supported RFCs,  Prev: System Architecture,  Up: Overview

1.3 Supported Platforms
=======================

Currently Quagga supports GNU/Linux and BSD. Porting Quagga to other
platforms is not too difficult as platform dependent code should most be
limited to the 'zebra' daemon.  Protocol daemons are mostly platform
independent.  Please let us know when you find out Quagga runs on a
platform which is not listed below.

   The list of officially supported platforms are listed below.  Note
that Quagga may run correctly on other platforms, and may run with
partial functionality on further platforms.


   * GNU/Linux
   * FreeBSD
   * NetBSD
   * OpenBSD

   Versions of these platforms that are older than around 2 years from
the point of their original release (in case of GNU/Linux, this is since
the kernel's release on kernel.org) may need some work.  Similarly, the
following platforms may work with some effort:


   * Solaris
   * Mac OSX

   Also note that, in particular regarding proprietary platforms,
compiler and C library choice will affect Quagga.  Only recent versions
of the following C compilers are well-tested:


   * GNU's GCC
   * LLVM's clang
   * Intel's ICC

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File: quagga.info,  Node: Supported RFCs,  Next: How to get Quagga,  Prev: Supported Platforms,  Up: Overview

1.4 Supported RFCs
==================

Below is the list of currently supported RFC's.

RFC1058
     'Routing Information Protocol. C.L. Hedrick. Jun-01-1988.'

RF2082
     'RIP-2 MD5 Authentication. F. Baker, R. Atkinson. January 1997.'

RFC2453
     'RIP Version 2. G. Malkin. November 1998.'

RFC2080
     'RIPng for IPv6. G. Malkin, R. Minnear. January 1997.'

RFC2328
     'OSPF Version 2. J. Moy. April 1998.'

RFC2370
     'The OSPF Opaque LSA Option R. Coltun. July 1998.'

RFC3101
     'The OSPF Not-So-Stubby Area (NSSA) Option P. Murphy. January
     2003.'

RFC2740
     'OSPF for IPv6. R. Coltun, D. Ferguson, J. Moy. December 1999.'

RFC1771
     'A Border Gateway Protocol 4 (BGP-4). Y. Rekhter & T. Li. March
     1995.'

RFC1965
     'Autonomous System Confederations for BGP. P. Traina. June 1996.'

RFC1997
     'BGP Communities Attribute. R. Chandra, P. Traina & T. Li. August
     1996.'

RFC2545
     'Use of BGP-4 Multiprotocol Extensions for IPv6 Inter-Domain
     Routing. P. Marques, F. Dupont. March 1999.'

RFC2796
     'BGP Route Reflection An alternative to full mesh IBGP. T. Bates &
     R. Chandrasekeran. June 1996.'

RFC2858
     'Multiprotocol Extensions for BGP-4. T. Bates, Y. Rekhter, R.
     Chandra, D. Katz. June 2000.'

RFC2842
     'Capabilities Advertisement with BGP-4. R. Chandra, J. Scudder. May
     2000.'

RFC3137
     'OSPF Stub Router Advertisement, A. Retana, L. Nguyen, R. White, A.
     Zinin, D. McPherson. June 2001'

   When SNMP support is enabled, below RFC is also supported.

RFC1227
     'SNMP MUX protocol and MIB. M.T. Rose. May-01-1991.'

RFC1657
     'Definitions of Managed Objects for the Fourth Version of the
     Border Gateway Protocol (BGP-4) using SMIv2. S. Willis, J. Burruss,
     J. Chu, Editor. July 1994.'

RFC1724
     'RIP Version 2 MIB Extension. G. Malkin & F. Baker. November 1994.'

RFC1850
     'OSPF Version 2 Management Information Base. F. Baker, R. Coltun.
     November 1995.'

RFC2741
     'Agent Extensibility (AgentX) Protocol. M. Daniele, B. Wijnen.
     January 2000.'

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1.5 How to get Quagga
=====================

The official Quagga web-site is located at:

   <http://www.quagga.net/>

   and contains further information, as well as links to additional
resources.

   Quagga (http://www.quagga.net/) is a fork of GNU Zebra, whose
web-site is located at:

   <http://www.zebra.org/>.

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1.6 Mailing List
================

There is a mailing list for discussions about Quagga.  If you have any
comments or suggestions to Quagga, please subscribe to:

   <http://lists.quagga.net/mailman/listinfo/quagga-users>.

   The Quagga site has further information on the available mailing
lists, see:

   <http://www.quagga.net/lists.php>

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1.7 Bug Reports
===============

If you think you have found a bug, please send a bug report to:

   <http://bugzilla.quagga.net>

   When you send a bug report, please be careful about the points below.

   * Please note what kind of OS you are using.  If you use the IPv6
     stack please note that as well.
   * Please show us the results of 'netstat -rn' and 'ifconfig -a'.
     Information from zebra's VTY command 'show ip route' will also be
     helpful.
   * Please send your configuration file with the report.  If you
     specify arguments to the configure script please note that too.

   Bug reports are very important for us to improve the quality of
Quagga.  Quagga is still in the development stage, but please don't
hesitate to send a bug report to <http://bugzilla.quagga.net>.

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File: quagga.info,  Node: Installation,  Next: Basic commands,  Prev: Overview,  Up: Top

2 Installation
**************

There are three steps for installing the software: configuration,
compilation, and installation.

* Menu:

* Configure the Software::
* Build the Software::
* Install the Software::

   The easiest way to get Quagga running is to issue the following
commands:

     % configure
     % make
     % make install

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File: quagga.info,  Node: Configure the Software,  Next: Build the Software,  Up: Installation

2.1 Configure the Software
==========================

* Menu:

* The Configure script and its options::
* Least-Privilege support::
* Linux notes::

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File: quagga.info,  Node: The Configure script and its options,  Next: Least-Privilege support,  Up: Configure the Software

2.1.1 The Configure script and its options
------------------------------------------

Quagga has an excellent configure script which automatically detects
most host configurations.  There are several additional configure
options you can use to turn off IPv6 support, to disable the compilation
of specific daemons, and to enable SNMP support.

'--disable-ipv6'
     Turn off IPv6 related features and daemons.  Quagga configure
     script automatically detects IPv6 stack.  But sometimes you might
     want to disable IPv6 support of Quagga.
'--disable-zebra'
     Do not build zebra daemon.
'--disable-ripd'
     Do not build ripd.
'--disable-ripngd'
     Do not build ripngd.
'--disable-ospfd'
     Do not build ospfd.
'--disable-ospf6d'
     Do not build ospf6d.
'--disable-bgpd'
     Do not build bgpd.
'--disable-bgp-announce'
     Make 'bgpd' which does not make bgp announcements at all.  This
     feature is good for using 'bgpd' as a BGP announcement listener.
'--enable-netlink'
     Force to enable GNU/Linux netlink interface.  Quagga configure
     script detects netlink interface by checking a header file.  When
     the header file does not match to the current running kernel,
     configure script will not turn on netlink support.
'--enable-snmp'
     Enable SNMP support.  By default, SNMP support is disabled.
'--disable-opaque-lsa'
     Disable support for Opaque LSAs (RFC2370) in ospfd.
'--disable-ospfapi'
     Disable support for OSPF-API, an API to interface directly with
     ospfd.  OSPF-API is enabled if -enable-opaque-lsa is set.
'--disable-ospfclient'
     Disable building of the example OSPF-API client.
'--disable-ospf-te'
     Disable support for OSPF Traffic Engineering Extension (RFC3630)
     this requires support for Opaque LSAs.
'--disable-ospf-ri'
     Disable support for OSPF Router Information (RFC4970 & RFC5088)
     this requires support for Opaque LSAs and Traffic Engineering.
'--enable-isisd'
     Build isisd.
'--enable-isis-topology'
     Enable IS-IS topology generator.
'--enable-isis-te'
     Enable Traffic Engineering Extension for ISIS (RFC5305)
'--enable-multipath=ARG'
     Enable support for Equal Cost Multipath.  ARG is the maximum number
     of ECMP paths to allow, set to 0 to allow unlimited number of
     paths.
'--disable-rtadv'
     Disable support IPV6 router advertisement in zebra.
'--enable-gcc-rdynamic'
     Pass the '-rdynamic' option to the linker driver.  This is in most
     cases neccessary for getting usable backtraces.  This option
     defaults to on if the compiler is detected as gcc, but giving an
     explicit enable/disable is suggested.
'--enable-backtrace'
     Controls backtrace support for the crash handlers.  This is
     autodetected by default.  Using the switch will enforce the
     requested behaviour, failing with an error if support is requested
     but not available.  On BSD systems, this needs libexecinfo, while
     on glibc support for this is part of libc itself.

   You may specify any combination of the above options to the configure
script.  By default, the executables are placed in '/usr/local/sbin' and
the configuration files in '/usr/local/etc'.  The '/usr/local/'
installation prefix and other directories may be changed using the
following options to the configuration script.

'--prefix=PREFIX'
     Install architecture-independent files in PREFIX [/usr/local].
'--sysconfdir=DIR'
     Look for configuration files in DIR [PREFIX/etc].  Note that sample
     configuration files will be installed here.
'--localstatedir=DIR'
     Configure zebra to use DIR for local state files, such as pid files
     and unix sockets.

     % ./configure --disable-ipv6

   This command will configure zebra and the routing daemons.

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File: quagga.info,  Node: Least-Privilege support,  Next: Linux notes,  Prev: The Configure script and its options,  Up: Configure the Software

2.1.2 Least-Privilege support
-----------------------------

Additionally, you may configure zebra to drop its elevated privileges
shortly after startup and switch to another user.  The configure script
will automatically try to configure this support.  There are three
configure options to control the behaviour of Quagga daemons.

'--enable-user=USER'
     Switch to user ARG shortly after startup, and run as user ARG in
     normal operation.
'--enable-group=GROUP'
     Switch real and effective group to GROUP shortly after startup.
'--enable-vty-group=GROUP'
     Create Unix Vty sockets (for use with vtysh) with group owndership
     set to GROUP.  This allows one to create a seperate group which is
     restricted to accessing only the Vty sockets, hence allowing one to
     delegate this group to individual users, or to run vtysh setgid to
     this group.

   The default user and group which will be configured is 'quagga' if no
user or group is specified.  Note that this user or group requires write
access to the local state directory (see -localstatedir) and requires at
least read access, and write access if you wish to allow daemons to
write out their configuration, to the configuration directory (see
-sysconfdir).

   On systems which have the 'libcap' capabilities manipulation library
(currently only linux), the quagga system will retain only minimal
capabilities required, further it will only raise these capabilities for
brief periods.  On systems without libcap, quagga will run as the user
specified and only raise its uid back to uid 0 for brief periods.

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File: quagga.info,  Node: Linux notes,  Prev: Least-Privilege support,  Up: Configure the Software

2.1.3 Linux Notes
-----------------

There are several options available only to GNU/Linux systems: (1).  If
you use GNU/Linux, make sure that the current kernel configuration is
what you want.  Quagga will run with any kernel configuration but some
recommendations do exist.

CONFIG_NETLINK
     Kernel/User netlink socket.  This is a brand new feature which
     enables an advanced interface between the Linux kernel and zebra
     (*note Kernel Interface::).

CONFIG_RTNETLINK
     Routing messages.  This makes it possible to receive netlink
     routing messages.  If you specify this option, 'zebra' can detect
     routing information updates directly from the kernel (*note Kernel
     Interface::).

CONFIG_IP_MULTICAST
     IP: multicasting.  This option should be specified when you use
     'ripd' (*note RIP::) or 'ospfd' (*note OSPFv2::) because these
     protocols use multicast.

   IPv6 support has been added in GNU/Linux kernel version 2.2.  If you
try to use the Quagga IPv6 feature on a GNU/Linux kernel, please make
sure the following libraries have been installed.  Please note that
these libraries will not be needed when you uses GNU C library 2.1 or
upper.

'inet6-apps'
     The 'inet6-apps' package includes basic IPv6 related libraries such
     as 'inet_ntop' and 'inet_pton'.  Some basic IPv6 programs such as
     'ping', 'ftp', and 'inetd' are also included.  The 'inet-apps' can
     be found at <ftp://ftp.inner.net/pub/ipv6/>.

'net-tools'
     The 'net-tools' package provides an IPv6 enabled interface and
     routing utility.  It contains 'ifconfig', 'route', 'netstat', and
     other tools.  'net-tools' may be found at
     <http://www.tazenda.demon.co.uk/phil/net-tools/>.

   ---------- Footnotes ----------

   (1) GNU/Linux has very flexible kernel configuration features

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File: quagga.info,  Node: Build the Software,  Next: Install the Software,  Prev: Configure the Software,  Up: Installation

2.2 Build the Software
======================

After configuring the software, you will need to compile it for your
system.  Simply issue the command 'make' in the root of the source
directory and the software will be compiled.  If you have *any* problems
at this stage, be certain to send a bug report *Note Bug Reports::.

     % ./configure
     .
     .
     .
     ./configure output
     .
     .
     .
     % make

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File: quagga.info,  Node: Install the Software,  Prev: Build the Software,  Up: Installation

2.3 Install the Software
========================

Installing the software to your system consists of copying the compiled
programs and supporting files to a standard location.  After the
installation process has completed, these files have been copied from
your work directory to '/usr/local/bin', and '/usr/local/etc'.

   To install the Quagga suite, issue the following command at your
shell prompt: 'make install'.

     %
     % make install
     %

   Quagga daemons have their own terminal interface or VTY. After
installation, you have to setup each beast's port number to connect to
them.  Please add the following entries to '/etc/services'.

     zebrasrv      2600/tcp               # zebra service
     zebra         2601/tcp               # zebra vty
     ripd          2602/tcp               # RIPd vty
     ripngd        2603/tcp               # RIPngd vty
     ospfd         2604/tcp               # OSPFd vty
     bgpd          2605/tcp               # BGPd vty
     ospf6d        2606/tcp               # OSPF6d vty
     ospfapi       2607/tcp               # ospfapi
     isisd         2608/tcp               # ISISd vty
     pimd          2611/tcp               # PIMd vty
     nhrpd         2612/tcp               # nhrpd vty

   If you use a FreeBSD newer than 2.2.8, the above entries are already
added to '/etc/services' so there is no need to add it.  If you specify
a port number when starting the daemon, these entries may not be needed.

   You may need to make changes to the config files in
'/etc/quagga/*.conf'.  *Note Config Commands::.

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File: quagga.info,  Node: Basic commands,  Next: Zebra,  Prev: Installation,  Up: Top

3 Basic commands
****************

There are five routing daemons in use, and there is one manager daemon.
These daemons may be located on separate machines from the manager
daemon.  Each of these daemons will listen on a particular port for
incoming VTY connections.  The routing daemons are:

   * 'ripd', 'ripngd', 'ospfd', 'ospf6d', 'bgpd'
   * 'zebra'

   The following sections discuss commands common to all the routing
daemons.

* Menu:

* Config Commands::             Commands used in config files
* Terminal Mode Commands::      Common commands used in a VTY
* Common Invocation Options::   Starting the daemons
* Virtual Terminal Interfaces:: Interacting with the daemons

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File: quagga.info,  Node: Config Commands,  Next: Terminal Mode Commands,  Up: Basic commands

3.1 Config Commands
===================

* Menu:

* Basic Config Commands::       Some of the generic config commands
* Sample Config File::          An example config file

In a config file, you can write the debugging options, a vty's password,
routing daemon configurations, a log file name, and so forth.  This
information forms the initial command set for a routing beast as it is
starting.

   Config files are generally found in:

     '/etc/quagga/*.conf'

   Each of the daemons has its own config file.  For example, zebra's
default config file name is:

     '/etc/quagga/zebra.conf'

   The daemon name plus '.conf' is the default config file name.  You
can specify a config file using the '-f' or '--config-file' options when
starting the daemon.

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File: quagga.info,  Node: Basic Config Commands,  Next: Sample Config File,  Up: Config Commands

3.1.1 Basic Config Commands
---------------------------

 -- Command: hostname HOSTNAME
     Set hostname of the router.

 -- Command: password PASSWORD
     Set password for vty interface.  If there is no password, a vty
     won't accept connections.

 -- Command: enable password PASSWORD
     Set enable password.

 -- Command: log trap LEVEL
 -- Command: no log trap
     These commands are deprecated and are present only for historical
     compatibility.  The log trap command sets the current logging level
     for all enabled logging destinations, and it sets the default for
     all future logging commands that do not specify a level.  The
     normal default logging level is debugging.  The 'no' form of the
     command resets the default level for future logging commands to
     debugging, but it does not change the logging level of existing
     logging destinations.

 -- Command: log stdout
 -- Command: log stdout LEVEL
 -- Command: no log stdout
     Enable logging output to stdout.  If the optional second argument
     specifying the logging level is not present, the default logging
     level (typically debugging, but can be changed using the deprecated
     'log trap' command) will be used.  The 'no' form of the command
     disables logging to stdout.  The 'level' argument must have one of
     these values: emergencies, alerts, critical, errors, warnings,
     notifications, informational, or debugging.  Note that the existing
     code logs its most important messages with severity 'errors'.

 -- Command: log file FILENAME
 -- Command: log file FILENAME LEVEL
 -- Command: no log file
     If you want to log into a file, please specify 'filename' as in
     this example:
          log file /var/log/quagga/bgpd.log informational
     If the optional second argument specifying the logging level is not
     present, the default logging level (typically debugging, but can be
     changed using the deprecated 'log trap' command) will be used.  The
     'no' form of the command disables logging to a file.

     Note: if you do not configure any file logging, and a daemon
     crashes due to a signal or an assertion failure, it will attempt to
     save the crash information in a file named /var/tmp/quagga.<daemon
     name>.crashlog.  For security reasons, this will not happen if the
     file exists already, so it is important to delete the file after
     reporting the crash information.

 -- Command: log syslog
 -- Command: log syslog LEVEL
 -- Command: no log syslog
     Enable logging output to syslog.  If the optional second argument
     specifying the logging level is not present, the default logging
     level (typically debugging, but can be changed using the deprecated
     'log trap' command) will be used.  The 'no' form of the command
     disables logging to syslog.

 -- Command: log monitor
 -- Command: log monitor LEVEL
 -- Command: no log monitor
     Enable logging output to vty terminals that have enabled logging
     using the 'terminal monitor' command.  By default, monitor logging
     is enabled at the debugging level, but this command (or the
     deprecated 'log trap' command) can be used to change the monitor
     logging level.  If the optional second argument specifying the
     logging level is not present, the default logging level (typically
     debugging, but can be changed using the deprecated 'log trap'
     command) will be used.  The 'no' form of the command disables
     logging to terminal monitors.

 -- Command: log facility FACILITY
 -- Command: no log facility
     This command changes the facility used in syslog messages.  The
     default facility is 'daemon'.  The 'no' form of the command resets
     the facility to the default 'daemon' facility.

 -- Command: log record-priority
 -- Command: no log record-priority
     To include the severity in all messages logged to a file, to
     stdout, or to a terminal monitor (i.e.  anything except syslog),
     use the 'log record-priority' global configuration command.  To
     disable this option, use the 'no' form of the command.  By default,
     the severity level is not included in logged messages.  Note: some
     versions of syslogd (including Solaris) can be configured to
     include the facility and level in the messages emitted.

 -- Command: log timestamp precision <0-6>
 -- Command: no log timestamp precision
     This command sets the precision of log message timestamps to the
     given number of digits after the decimal point.  Currently, the
     value must be in the range 0 to 6 (i.e.  the maximum precision is
     microseconds).  To restore the default behavior (1-second
     accuracy), use the 'no' form of the command, or set the precision
     explicitly to 0.

          log timestamp precision 3

     In this example, the precision is set to provide timestamps with
     millisecond accuracy.

 -- Command: log commands
     This command enables the logging of all commands typed by a user to
     all enabled log destinations.  The note that logging includes full
     command lines, including passwords.  Once set, command logging can
     only be turned off by restarting the daemon.

 -- Command: service password-encryption
     Encrypt password.

 -- Command: service advanced-vty
     Enable advanced mode VTY.

 -- Command: service terminal-length <0-512>
     Set system wide line configuration.  This configuration command
     applies to all VTY interfaces.

 -- Command: line vty
     Enter vty configuration mode.

 -- Command: banner motd default
     Set default motd string.

 -- Command: no banner motd
     No motd banner string will be printed.

 -- Line Command: exec-timeout MINUTE
 -- Line Command: exec-timeout MINUTE SECOND
     Set VTY connection timeout value.  When only one argument is
     specified it is used for timeout value in minutes.  Optional second
     argument is used for timeout value in seconds.  Default timeout
     value is 10 minutes.  When timeout value is zero, it means no
     timeout.

 -- Line Command: no exec-timeout
     Do not perform timeout at all.  This command is as same as
     'exec-timeout 0 0'.

 -- Line Command: access-class ACCESS-LIST
     Restrict vty connections with an access list.

\1f
File: quagga.info,  Node: Sample Config File,  Prev: Basic Config Commands,  Up: Config Commands

3.1.2 Sample Config File
------------------------

Below is a sample configuration file for the zebra daemon.

     !
     ! Zebra configuration file
     !
     hostname Router
     password zebra
     enable password zebra
     !
     log stdout
     !
     !

   '!'  and '#' are comment characters.  If the first character of the
word is one of the comment characters then from the rest of the line
forward will be ignored as a comment.

     password zebra!password

   If a comment character is not the first character of the word, it's a
normal character.  So in the above example '!'  will not be regarded as
a comment and the password is set to 'zebra!password'.

\1f
File: quagga.info,  Node: Terminal Mode Commands,  Next: Common Invocation Options,  Prev: Config Commands,  Up: Basic commands

3.2 Terminal Mode Commands
==========================

 -- Command: write terminal
     Displays the current configuration to the vty interface.

 -- Command: write file
     Write current configuration to configuration file.

 -- Command: configure terminal
     Change to configuration mode.  This command is the first step to
     configuration.

 -- Command: terminal length <0-512>
     Set terminal display length to <0-512>.  If length is 0, no display
     control is performed.

 -- Command: who
     Show a list of currently connected vty sessions.

 -- Command: list
     List all available commands.

 -- Command: show version
     Show the current version of Quagga and its build host information.

 -- Command: show logging
     Shows the current configuration of the logging system.  This
     includes the status of all logging destinations.

 -- Command: logmsg LEVEL MESSAGE
     Send a message to all logging destinations that are enabled for
     messages of the given severity.

\1f
File: quagga.info,  Node: Common Invocation Options,  Next: Virtual Terminal Interfaces,  Prev: Terminal Mode Commands,  Up: Basic commands

3.3 Common Invocation Options
=============================

These options apply to all Quagga daemons.

'-d'
'--daemon'
     Runs in daemon mode.

'-f FILE'
'--config_file=FILE'
     Set configuration file name.

'-h'
'--help'
     Display this help and exit.

'-i FILE'
'--pid_file=FILE'

     Upon startup the process identifier of the daemon is written to a
     file, typically in '/var/run'.  This file can be used by the init
     system to implement commands such as '.../init.d/zebra status',
     '.../init.d/zebra restart' or '.../init.d/zebra stop'.

     The file name is an run-time option rather than a configure-time
     option so that multiple routing daemons can be run simultaneously.
     This is useful when using Quagga to implement a routing looking
     glass.  One machine can be used to collect differing routing views
     from differing points in the network.

'-A ADDRESS'
'--vty_addr=ADDRESS'
     Set the VTY local address to bind to.  If set, the VTY socket will
     only be bound to this address.

'-P PORT'
'--vty_port=PORT'
     Set the VTY TCP port number.  If set to 0 then the TCP VTY sockets
     will not be opened.

'-u USER'
'--vty_addr=USER'
     Set the user and group to run as.

'-v'
'--version'
     Print program version.

\1f
File: quagga.info,  Node: Virtual Terminal Interfaces,  Prev: Common Invocation Options,  Up: Basic commands

3.4 Virtual Terminal Interfaces
===============================

VTY - Virtual Terminal [aka TeletYpe] Interface is a command line
interface (CLI) for user interaction with the routing daemon.

* Menu:

* VTY Overview::                Basics about VTYs
* VTY Modes::                   View, Enable, and Other VTY modes
* VTY CLI Commands::            Commands for movement, edition, and management

\1f
File: quagga.info,  Node: VTY Overview,  Next: VTY Modes,  Up: Virtual Terminal Interfaces

3.4.1 VTY Overview
------------------

VTY stands for Virtual TeletYpe interface.  It means you can connect to
the daemon via the telnet protocol.

   To enable a VTY interface, you have to setup a VTY password.  If
there is no VTY password, one cannot connect to the VTY interface at
all.

     % telnet localhost 2601
     Trying 127.0.0.1...
     Connected to localhost.
     Escape character is '^]'.

     Hello, this is Quagga (version 1.2.3)
     Copyright (C) 1999-2005 Kunihiro Ishiguro, et al.

     User Access Verification

     Password: XXXXX
     Router> ?
       enable            Turn on privileged commands
       exit              Exit current mode and down to previous mode
       help              Description of the interactive help system
       list              Print command list
       show              Show running system information
       who               Display who is on a vty
     Router> enable
     Password: XXXXX
     Router# configure terminal
     Router(config)# interface eth0
     Router(config-if)# ip address 10.0.0.1/8
     Router(config-if)# ^Z
     Router#

   '?'  is very useful for looking up commands.

\1f
File: quagga.info,  Node: VTY Modes,  Next: VTY CLI Commands,  Prev: VTY Overview,  Up: Virtual Terminal Interfaces

3.4.2 VTY Modes
---------------

There are three basic VTY modes:

* Menu:

* VTY View Mode::               Mode for read-only interaction
* VTY Enable Mode::             Mode for read-write interaction
* VTY Other Modes::             Special modes (tftp, etc)

   There are commands that may be restricted to specific VTY modes.

\1f
File: quagga.info,  Node: VTY View Mode,  Next: VTY Enable Mode,  Up: VTY Modes

3.4.2.1 VTY View Mode
.....................

This mode is for read-only access to the CLI. One may exit the mode by
leaving the system, or by entering 'enable' mode.

\1f
File: quagga.info,  Node: VTY Enable Mode,  Next: VTY Other Modes,  Prev: VTY View Mode,  Up: VTY Modes

3.4.2.2 VTY Enable Mode
.......................

This mode is for read-write access to the CLI. One may exit the mode by
leaving the system, or by escaping to view mode.

\1f
File: quagga.info,  Node: VTY Other Modes,  Prev: VTY Enable Mode,  Up: VTY Modes

3.4.2.3 VTY Other Modes
.......................

This page is for describing other modes.

\1f
File: quagga.info,  Node: VTY CLI Commands,  Prev: VTY Modes,  Up: Virtual Terminal Interfaces

3.4.3 VTY CLI Commands
----------------------

Commands that you may use at the command-line are described in the
following three subsubsections.

* Menu:

* CLI Movement Commands::       Commands for moving the cursor about
* CLI Editing Commands::        Commands for changing text
* CLI Advanced Commands::       Other commands, session management and so on

\1f
File: quagga.info,  Node: CLI Movement Commands,  Next: CLI Editing Commands,  Up: VTY CLI Commands

3.4.3.1 CLI Movement Commands
.............................

These commands are used for moving the CLI cursor.  The <C> character
means press the Control Key.

'C-f'
'<RIGHT>'
     Move forward one character.

'C-b'
'<LEFT>'
     Move backward one character.

'M-f'
     Move forward one word.

'M-b'
     Move backward one word.

'C-a'
     Move to the beginning of the line.

'C-e'
     Move to the end of the line.

\1f
File: quagga.info,  Node: CLI Editing Commands,  Next: CLI Advanced Commands,  Prev: CLI Movement Commands,  Up: VTY CLI Commands

3.4.3.2 CLI Editing Commands
............................

These commands are used for editing text on a line.  The <C> character
means press the Control Key.

'C-h'
'<DEL>'
     Delete the character before point.

'C-d'
     Delete the character after point.

'M-d'
     Forward kill word.

'C-w'
     Backward kill word.

'C-k'
     Kill to the end of the line.

'C-u'
     Kill line from the beginning, erasing input.

'C-t'
     Transpose character.

'C-v'
     Interpret following character literally.  Do not treat it
     specially.  This can be used to, e.g., type in a literal '?' rather
     than do help completion.

\1f
File: quagga.info,  Node: CLI Advanced Commands,  Prev: CLI Editing Commands,  Up: VTY CLI Commands

3.4.3.3 CLI Advanced Commands
.............................

There are several additional CLI commands for command line completions,
insta-help, and VTY session management.

'C-c'
     Interrupt current input and moves to the next line.

'C-z'
     End current configuration session and move to top node.

'C-n'
'<DOWN>'
     Move down to next line in the history buffer.

'C-p'
'<UP>'
     Move up to previous line in the history buffer.

'TAB'
     Use command line completion by typing <TAB>.

'?'
     You can use command line help by typing 'help' at the beginning of
     the line.  Typing '?' at any point in the line will show possible
     completions.

     To enter an actual '?' character rather show completions, e.g.  to
     enter into a regexp, use '<C>-v ?'.

\1f
File: quagga.info,  Node: Zebra,  Next: RIP,  Prev: Basic commands,  Up: Top

4 Zebra
*******

'zebra' is an IP routing manager.  It provides kernel routing table
updates, interface lookups, and redistribution of routes between
different routing protocols.

* Menu:

* Invoking zebra::              Running the program
* Interface Commands::          Commands for zebra interfaces
* Static Route Commands::       Commands for adding static routes
* Multicast RIB Commands::      Commands for controlling MRIB behavior
* zebra Route Filtering::       Commands for zebra route filtering
* zebra FIB push interface::    Interface to optional FPM component
* zebra Terminal Mode Commands::  Commands for zebra's VTY

\1f
File: quagga.info,  Node: Invoking zebra,  Next: Interface Commands,  Up: Zebra

4.1 Invoking zebra
==================

Besides the common invocation options (*note Common Invocation
Options::), the 'zebra' specific invocation options are listed below.

'-b'
'--batch'
     Runs in batch mode.  'zebra' parses configuration file and
     terminates immediately.

'-k'
'--keep_kernel'
     When zebra starts up, don't delete old self inserted routes.

'-r'
'--retain'
     When program terminates, retain routes added by zebra.

\1f
File: quagga.info,  Node: Interface Commands,  Next: Static Route Commands,  Prev: Invoking zebra,  Up: Zebra

4.2 Interface Commands
======================

* Menu:

* Standard Commands::
* Link Parameters Commands::            

\1f
File: quagga.info,  Node: Standard Commands,  Next: Link Parameters Commands,  Up: Interface Commands

4.2.1 Standard Commands
-----------------------

 -- Command: interface IFNAME

 -- Interface Command: shutdown
 -- Interface Command: no shutdown
     Up or down the current interface.

 -- Interface Command: ip address ADDRESS/PREFIX
 -- Interface Command: ipv6 address ADDRESS/PREFIX
 -- Interface Command: no ip address ADDRESS/PREFIX
 -- Interface Command: no ipv6 address ADDRESS/PREFIX
     Set the IPv4 or IPv6 address/prefix for the interface.

 -- Interface Command: ip address ADDRESS/PREFIX secondary
 -- Interface Command: no ip address ADDRESS/PREFIX secondary
     Set the secondary flag for this address.  This causes ospfd to not
     treat the address as a distinct subnet.

 -- Interface Command: description DESCRIPTION ...
     Set description for the interface.

 -- Interface Command: multicast
 -- Interface Command: no multicast
     Enable or disables multicast flag for the interface.

 -- Interface Command: bandwidth <1-10000000>
 -- Interface Command: no bandwidth <1-10000000>
     Set bandwidth value of the interface in kilobits/sec.  This is for
     calculating OSPF cost.  This command does not affect the actual
     device configuration.

 -- Interface Command: link-detect
 -- Interface Command: no link-detect
     Enable/disable link-detect on platforms which support this.
     Currently only Linux and Solaris, and only where network interface
     drivers support reporting link-state via the IFF_RUNNING flag.

\1f
File: quagga.info,  Node: Link Parameters Commands,  Prev: Standard Commands,  Up: Interface Commands

4.2.2 Link Parameters Commands
------------------------------

 -- Interface Command: link-params
 -- Interface Command: no link-param
     Enter into the link parameters sub node.  At least 'enable' must be
     set to activate the link parameters, and consequently Traffic
     Engineering on this interface.  MPLS-TE must be enable at the OSPF
     (*note OSPF Traffic Engineering::) or ISIS (*note ISIS Traffic
     Engineering::) router level in complement to this.  Disable link
     parameters for this interface.

   Under link parameter statement, the following commands set the
different TE values:

 -- link-params: enable
     Enable link parameters for this interface.

 -- link-params: metric <0-4294967295>
 -- link-params: max-bw BANDWIDTH
 -- link-params: max-rsv-bw BANDWIDTH
 -- link-params: unrsv-bw <0-7> BANDWIDTH
 -- link-params: admin-grp BANDWIDTH
     These commands specifies the Traffic Engineering parameters of the
     interface in conformity to RFC3630 (OSPF) or RFC5305 (ISIS). There
     are respectively the TE Metric (different from the OSPF or ISIS
     metric), Maximum Bandwidth (interface speed by default), Maximum
     Reservable Bandwidth, Unreserved Bandwidth for each 0-7 priority
     and Admin Group (ISIS) or Resource Class/Color (OSPF).

     Note that BANDWIDTH are specified in IEEE floating point format and
     express in Bytes/second.

 -- link-param: delay <0-16777215> [min <0-16777215> | max <0-16777215>]
 -- link-param: delay-variation <0-16777215>
 -- link-param: packet-loss PERCENTAGE
 -- link-param: res-bw BANDWIDTH
 -- link-param: ava-bw BANDWIDTH
 -- link-param: use-bw BANDWIDTH
     These command specifies additionnal Traffic Engineering parameters
     of the interface in conformity to
     draft-ietf-ospf-te-metrics-extension-05.txt and
     draft-ietf-isis-te-metrics-extension-03.txt.  There are
     respectively the delay, jitter, loss, available bandwidth,
     reservable bandwidth and utilized bandwidth.

     Note that BANDWIDTH are specified in IEEE floating point format and
     express in Bytes/second.  Delays and delay variation are express in
     micro-second (µs).  Loss is specified in PERCENTAGE ranging from 0
     to 50.331642% by step of 0.000003.

 -- link-param: neighbor <A.B.C.D> as <0-65535>
 -- link-param: no neighbor
     Specifies the remote ASBR IP address and Autonomous System (AS)
     number for InterASv2 link in OSPF (RFC5392).  Note that this option
     is not yet supported for ISIS (RFC5316).

\1f
File: quagga.info,  Node: Static Route Commands,  Next: Multicast RIB Commands,  Prev: Interface Commands,  Up: Zebra

4.3 Static Route Commands
=========================

Static routing is a very fundamental feature of routing technology.  It
defines static prefix and gateway.

 -- Command: ip route NETWORK GATEWAY
     NETWORK is destination prefix with format of A.B.C.D/M. GATEWAY is
     gateway for the prefix.  When GATEWAY is A.B.C.D format.  It is
     taken as a IPv4 address gateway.  Otherwise it is treated as an
     interface name.  If the interface name is NULL0 then zebra installs
     a blackhole route.

          ip route 10.0.0.0/8 10.0.0.2
          ip route 10.0.0.0/8 ppp0
          ip route 10.0.0.0/8 null0

     First example defines 10.0.0.0/8 static route with gateway
     10.0.0.2.  Second one defines the same prefix but with gateway to
     interface ppp0.  The third install a blackhole route.

 -- Command: ip route NETWORK NETMASK GATEWAY
     This is alternate version of above command.  When NETWORK is
     A.B.C.D format, user must define NETMASK value with A.B.C.D format.
     GATEWAY is same option as above command

          ip route 10.0.0.0 255.0.0.0 10.0.0.2
          ip route 10.0.0.0 255.0.0.0 ppp0
          ip route 10.0.0.0 255.0.0.0 null0

     These statements are equivalent to those in the previous example.

 -- Command: ip route NETWORK GATEWAY DISTANCE
     Installs the route with the specified distance.

   Multiple nexthop static route

     ip route 10.0.0.1/32 10.0.0.2
     ip route 10.0.0.1/32 10.0.0.3
     ip route 10.0.0.1/32 eth0

   If there is no route to 10.0.0.2 and 10.0.0.3, and interface eth0 is
reachable, then the last route is installed into the kernel.

   If zebra has been compiled with multipath support, and both 10.0.0.2
and 10.0.0.3 are reachable, zebra will install a multipath route via
both nexthops, if the platform supports this.

     zebra> show ip route
     S>  10.0.0.1/32 [1/0] via 10.0.0.2 inactive
                           via 10.0.0.3 inactive
       *                   is directly connected, eth0

     ip route 10.0.0.0/8 10.0.0.2
     ip route 10.0.0.0/8 10.0.0.3
     ip route 10.0.0.0/8 null0 255

   This will install a multihop route via the specified next-hops if
they are reachable, as well as a high-metric blackhole route, which can
be useful to prevent traffic destined for a prefix to match
less-specific routes (eg default) should the specified gateways not be
reachable.  Eg:

     zebra> show ip route 10.0.0.0/8
     Routing entry for 10.0.0.0/8
       Known via "static", distance 1, metric 0
         10.0.0.2 inactive
         10.0.0.3 inactive

     Routing entry for 10.0.0.0/8
       Known via "static", distance 255, metric 0
         directly connected, Null0

 -- Command: ipv6 route NETWORK GATEWAY
 -- Command: ipv6 route NETWORK GATEWAY DISTANCE
     These behave similarly to their ipv4 counterparts.

 -- Command: table TABLENO
     Select the primary kernel routing table to be used.  This only
     works for kernels supporting multiple routing tables (like
     GNU/Linux 2.2.x and later).  After setting TABLENO with this
     command, static routes defined after this are added to the
     specified table.

\1f
File: quagga.info,  Node: Multicast RIB Commands,  Next: zebra Route Filtering,  Prev: Static Route Commands,  Up: Zebra

4.4 Multicast RIB Commands
==========================

The Multicast RIB provides a separate table of unicast destinations
which is used for Multicast Reverse Path Forwarding decisions.  It is
used with a multicast source's IP address, hence contains not multicast
group addresses but unicast addresses.

   This table is fully separate from the default unicast table.
However, RPF lookup can include the unicast table.

   WARNING: RPF lookup results are non-responsive in this version of
Quagga, i.e.  multicast routing does not actively react to changes in
underlying unicast topology!

 -- Command: ip multicast rpf-lookup-mode MODE
 -- Command: no ip multicast rpf-lookup-mode [MODE]

     MODE sets the method used to perform RPF lookups.  Supported modes:

     'urib-only'
          Performs the lookup on the Unicast RIB. The Multicast RIB is
          never used.
     'mrib-only'
          Performs the lookup on the Multicast RIB. The Unicast RIB is
          never used.
     'mrib-then-urib'
          Tries to perform the lookup on the Multicast RIB. If any route
          is found, that route is used.  Otherwise, the Unicast RIB is
          tried.
     'lower-distance'
          Performs a lookup on the Multicast RIB and Unicast RIB each.
          The result with the lower administrative distance is used; if
          they're equal, the Multicast RIB takes precedence.
     'longer-prefix'
          Performs a lookup on the Multicast RIB and Unicast RIB each.
          The result with the longer prefix length is used; if they're
          equal, the Multicast RIB takes precedence.

     The 'mrib-then-urib' setting is the default behavior if nothing is
     configured.  If this is the desired behavior, it should be
     explicitly configured to make the configuration immune against
     possible changes in what the default behavior is.

     WARNING: Unreachable routes do not receive special treatment and do
     not cause fallback to a second lookup.

 -- Command: show ip rpf ADDR

     Performs a Multicast RPF lookup, as configured with 'ip multicast
     rpf-lookup-mode MODE'.  ADDR specifies the multicast source address
     to look up.

          > show ip rpf 192.0.2.1
          Routing entry for 192.0.2.0/24 using Unicast RIB
            Known via "kernel", distance 0, metric 0, best
            * 198.51.100.1, via eth0

     Indicates that a multicast source lookup for 192.0.2.1 would use an
     Unicast RIB entry for 192.0.2.0/24 with a gateway of 198.51.100.1.

 -- Command: show ip rpf

     Prints the entire Multicast RIB. Note that this is independent of
     the configured RPF lookup mode, the Multicast RIB may be printed
     yet not used at all.

 -- Command: ip mroute PREFIX NEXTHOP [DISTANCE]
 -- Command: no ip mroute PREFIX NEXTHOP [DISTANCE]

     Adds a static route entry to the Multicast RIB. This performs
     exactly as the 'ip route' command, except that it inserts the route
     in the Multicast RIB instead of the Unicast RIB.

\1f
File: quagga.info,  Node: zebra Route Filtering,  Next: zebra FIB push interface,  Prev: Multicast RIB Commands,  Up: Zebra

4.5 zebra Route Filtering
=========================

Zebra supports 'prefix-list' and 'route-map' to match routes received
from other quagga components.  The 'permit'/'deny' facilities provided
by these commands can be used to filter which routes zebra will install
in the kernel.

 -- Command: ip protocol PROTOCOL route-map ROUTEMAP
     Apply a route-map filter to routes for the specified protocol.
     PROTOCOL can be any or one of system, kernel, connected, static,
     rip, ripng, ospf, ospf6, isis, bgp, hsls.

 -- Route Map: set src ADDRESS
     Within a route-map, set the preferred source address for matching
     routes when installing in the kernel.

   The following creates a prefix-list that matches all addresses, a
route-map that sets the preferred source address, and applies the
route-map to all 'rip' routes.

     ip prefix-list ANY permit 0.0.0.0/0 le 32
     route-map RM1 permit 10
          match ip address prefix-list ANY
          set src 10.0.0.1

     ip protocol rip route-map RM1

\1f
File: quagga.info,  Node: zebra FIB push interface,  Next: zebra Terminal Mode Commands,  Prev: zebra Route Filtering,  Up: Zebra

4.6 zebra FIB push interface
============================

Zebra supports a 'FIB push' interface that allows an external component
to learn the forwarding information computed by the Quagga routing
suite.

   In Quagga, the Routing Information Base (RIB) resides inside zebra.
Routing protocols communicate their best routes to zebra, and zebra
computes the best route across protocols for each prefix.  This latter
information makes up the Forwarding Information Base (FIB). Zebra feeds
the FIB to the kernel, which allows the IP stack in the kernel to
forward packets according to the routes computed by Quagga.  The kernel
FIB is updated in an OS-specific way.  For example, the 'netlink'
interface is used on Linux, and route sockets are used on FreeBSD.

   The FIB push interface aims to provide a cross-platform mechanism to
support scenarios where the router has a forwarding path that is
distinct from the kernel, commonly a hardware-based fast path.  In these
cases, the FIB needs to be maintained reliably in the fast path as well.
We refer to the component that programs the forwarding plane (directly
or indirectly) as the Forwarding Plane Manager or FPM.

   The FIB push interface comprises of a TCP connection between zebra
and the FPM. The connection is initiated by zebra - that is, the FPM
acts as the TCP server.

   The relevant zebra code kicks in when zebra is configured with the
'--enable-fpm' flag.  Zebra periodically attempts to connect to the
well-known FPM port.  Once the connection is up, zebra starts sending
messages containing routes over the socket to the FPM. Zebra sends a
complete copy of the forwarding table to the FPM, including routes that
it may have picked up from the kernel.  The existing interaction of
zebra with the kernel remains unchanged - that is, the kernel continues
to receive FIB updates as before.

   The encapsulation header for the messages exchanged with the FPM is
defined by the file 'fpm/fpm.h' in the quagga tree.  The routes
themselves are encoded in netlink or protobuf format, with netlink being
the default.

   Protobuf is one of a number of new serialization formats wherein the
message schema is expressed in a purpose-built language.  Code for
encoding/decoding to/from the wire format is generated from the schema.
Protobuf messages can be extended easily while maintaining
backward-compatibility with older code.  Protobuf has the following
advantages over netlink:

   * Code for serialization/deserialization is generated automatically.
     This reduces the likelihood of bugs, allows third-party programs to
     be integrated quickly, and makes it easy to add fields.
   * The message format is not tied to an OS (Linux), and can be evolved
     independently.

   As mentioned before, zebra encodes routes sent to the FPM in netlink
format by default.  The format can be controlled via the '--fpm_format'
command-line option to zebra, which currently takes the values 'netlink'
and 'protobuf'.

   The zebra FPM interface uses replace semantics.  That is, if a 'route
add' message for a prefix is followed by another 'route add' message,
the information in the second message is complete by itself, and
replaces the information sent in the first message.

   If the connection to the FPM goes down for some reason, zebra sends
the FPM a complete copy of the forwarding table(s) when it reconnects.

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File: quagga.info,  Node: zebra Terminal Mode Commands,  Prev: zebra FIB push interface,  Up: Zebra

4.7 zebra Terminal Mode Commands
================================

 -- Command: show ip route
     Display current routes which zebra holds in its database.

          Router# show ip route
          Codes: K - kernel route, C - connected, S - static, R - RIP,
                 B - BGP * - FIB route.

          K* 0.0.0.0/0              203.181.89.241
          S  0.0.0.0/0              203.181.89.1
          C* 127.0.0.0/8            lo
          C* 203.181.89.240/28      eth0

 -- Command: show ipv6 route

 -- Command: show interface

 -- Command: show ip prefix-list [NAME]

 -- Command: show route-map [NAME]

 -- Command: show ip protocol

 -- Command: show ipforward
     Display whether the host's IP forwarding function is enabled or
     not.  Almost any UNIX kernel can be configured with IP forwarding
     disabled.  If so, the box can't work as a router.

 -- Command: show ipv6forward
     Display whether the host's IP v6 forwarding is enabled or not.

 -- Command: show zebra fpm stats
     Display statistics related to the zebra code that interacts with
     the optional Forwarding Plane Manager (FPM) component.

 -- Command: clear zebra fpm stats
     Reset statistics related to the zebra code that interacts with the
     optional Forwarding Plane Manager (FPM) component.

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File: quagga.info,  Node: RIP,  Next: RIPng,  Prev: Zebra,  Up: Top

5 RIP
*****

RIP - Routing Information Protocol is widely deployed interior gateway
protocol.  RIP was developed in the 1970s at Xerox Labs as part of the
XNS routing protocol.  RIP is a "distance-vector" protocol and is based
on the "Bellman-Ford" algorithms.  As a distance-vector protocol, RIP
router send updates to its neighbors periodically, thus allowing the
convergence to a known topology.  In each update, the distance to any
given network will be broadcasted to its neighboring router.

   'ripd' supports RIP version 2 as described in RFC2453 and RIP version
1 as described in RFC1058.

* Menu:

* Starting and Stopping ripd::  
* RIP Configuration::           
* RIP Version Control::
* How to Announce RIP route::   
* Filtering RIP Routes::        
* RIP Metric Manipulation::     
* RIP distance::                
* RIP route-map::               
* RIP Authentication::          
* RIP Timers::                  
* Show RIP Information::        
* RIP Debug Commands::          

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File: quagga.info,  Node: Starting and Stopping ripd,  Next: RIP Configuration,  Up: RIP

5.1 Starting and Stopping ripd
==============================

The default configuration file name of 'ripd''s is 'ripd.conf'.  When
invocation 'ripd' searches directory /etc/quagga.  If 'ripd.conf' is not
there next search current directory.

   RIP uses UDP port 520 to send and receive RIP packets.  So the user
must have the capability to bind the port, generally this means that the
user must have superuser privileges.  RIP protocol requires interface
information maintained by 'zebra' daemon.  So running 'zebra' is
mandatory to run 'ripd'.  Thus minimum sequence for running RIP is like
below:

     # zebra -d
     # ripd -d

   Please note that 'zebra' must be invoked before 'ripd'.

   To stop 'ripd'.  Please use 'kill `cat /var/run/ripd.pid`'.  Certain
signals have special meaningss to 'ripd'.

'SIGHUP'
     Reload configuration file 'ripd.conf'.  All configurations are
     reseted.  All routes learned so far are cleared and removed from
     routing table.
'SIGUSR1'
     Rotate 'ripd' logfile.
'SIGINT'
'SIGTERM'
     'ripd' sweeps all installed RIP routes then terminates properly.

   'ripd' invocation options.  Common options that can be specified
(*note Common Invocation Options::).

'-r'
'--retain'
     When the program terminates, retain routes added by 'ripd'.

* Menu:

* RIP netmask::                 

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File: quagga.info,  Node: RIP netmask,  Up: Starting and Stopping ripd

5.1.1 RIP netmask
-----------------

The netmask features of 'ripd' support both version 1 and version 2 of
RIP. Version 1 of RIP originally contained no netmask information.  In
RIP version 1, network classes were originally used to determine the
size of the netmask.  Class A networks use 8 bits of mask, Class B
networks use 16 bits of masks, while Class C networks use 24 bits of
mask.  Today, the most widely used method of a network mask is assigned
to the packet on the basis of the interface that received the packet.
Version 2 of RIP supports a variable length subnet mask (VLSM). By
extending the subnet mask, the mask can be divided and reused.  Each
subnet can be used for different purposes such as large to middle size
LANs and WAN links.  Quagga 'ripd' does not support the non-sequential
netmasks that are included in RIP Version 2.

   In a case of similar information with the same prefix and metric, the
old information will be suppressed.  Ripd does not currently support
equal cost multipath routing.

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File: quagga.info,  Node: RIP Configuration,  Next: RIP Version Control,  Prev: Starting and Stopping ripd,  Up: RIP

5.2 RIP Configuration
=====================

 -- Command: router rip
     The 'router rip' command is necessary to enable RIP. To disable
     RIP, use the 'no router rip' command.  RIP must be enabled before
     carrying out any of the RIP commands.

 -- Command: no router rip
     Disable RIP.

 -- RIP Command: network NETWORK
 -- RIP Command: no network NETWORK
     Set the RIP enable interface by NETWORK.  The interfaces which have
     addresses matching with NETWORK are enabled.

     This group of commands either enables or disables RIP interfaces
     between certain numbers of a specified network address.  For
     example, if the network for 10.0.0.0/24 is RIP enabled, this would
     result in all the addresses from 10.0.0.0 to 10.0.0.255 being
     enabled for RIP. The 'no network' command will disable RIP for the
     specified network.

 -- RIP Command: network IFNAME
 -- RIP Command: no network IFNAME
     Set a RIP enabled interface by IFNAME.  Both the sending and
     receiving of RIP packets will be enabled on the port specified in
     the 'network ifname' command.  The 'no network ifname' command will
     disable RIP on the specified interface.

 -- RIP Command: neighbor A.B.C.D
 -- RIP Command: no neighbor A.B.C.D
     Specify RIP neighbor.  When a neighbor doesn't understand
     multicast, this command is used to specify neighbors.  In some
     cases, not all routers will be able to understand multicasting,
     where packets are sent to a network or a group of addresses.  In a
     situation where a neighbor cannot process multicast packets, it is
     necessary to establish a direct link between routers.  The neighbor
     command allows the network administrator to specify a router as a
     RIP neighbor.  The 'no neighbor a.b.c.d' command will disable the
     RIP neighbor.

   Below is very simple RIP configuration.  Interface 'eth0' and
interface which address match to '10.0.0.0/8' are RIP enabled.

     !
     router rip
      network 10.0.0.0/8
      network eth0
     !

   Passive interface

 -- RIP command: passive-interface (IFNAME|default)
 -- RIP command: no passive-interface IFNAME
     This command sets the specified interface to passive mode.  On
     passive mode interface, all receiving packets are processed as
     normal and ripd does not send either multicast or unicast RIP
     packets except to RIP neighbors specified with 'neighbor' command.
     The interface may be specified as DEFAULT to make ripd default to
     passive on all interfaces.

     The default is to be passive on all interfaces.

   RIP split-horizon

 -- Interface command: ip split-horizon
 -- Interface command: no ip split-horizon
     Control split-horizon on the interface.  Default is 'ip
     split-horizon'.  If you don't perform split-horizon on the
     interface, please specify 'no ip split-horizon'.

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File: quagga.info,  Node: RIP Version Control,  Next: How to Announce RIP route,  Prev: RIP Configuration,  Up: RIP

5.3 RIP Version Control
=======================

RIP can be configured to send either Version 1 or Version 2 packets.
The default is to send RIPv2 while accepting both RIPv1 and RIPv2 (and
replying with packets of the appropriate version for REQUESTS /
triggered updates).  The version to receive and send can be specified
globally, and further overriden on a per-interface basis if needs be for
send and receive seperately (see below).

   It is important to note that RIPv1 can not be authenticated.
Further, if RIPv1 is enabled then RIP will reply to REQUEST packets,
sending the state of its RIP routing table to any remote routers that
ask on demand.  For a more detailed discussion on the security
implications of RIPv1 see *note RIP Authentication::.

 -- RIP Command: version VERSION
     Set RIP version to accept for reads and send.  VERSION can be
     either '1" or '2".

     Disabling RIPv1 by specifying version 2 is STRONGLY encouraged,
     *Note RIP Authentication::.  This may become the default in a
     future release.

     Default: Send Version 2, and accept either version.

 -- RIP Command: no version
     Reset the global version setting back to the default.

 -- Interface command: ip rip send version VERSION
     VERSION can be '1', '2' or '1 2'.

     This interface command overrides the global rip version setting,
     and selects which version of RIP to send packets with, for this
     interface specifically.  Choice of RIP Version 1, RIP Version 2, or
     both versions.  In the latter case, where '1 2' is specified,
     packets will be both broadcast and multicast.

     Default: Send packets according to the global version (version 2)

 -- Interface command: ip rip receive version VERSION
     VERSION can be '1', '2' or '1 2'.

     This interface command overrides the global rip version setting,
     and selects which versions of RIP packets will be accepted on this
     interface.  Choice of RIP Version 1, RIP Version 2, or both.

     Default: Accept packets according to the global setting (both 1 and
     2).

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File: quagga.info,  Node: How to Announce RIP route,  Next: Filtering RIP Routes,  Prev: RIP Version Control,  Up: RIP

5.4 How to Announce RIP route
=============================

 -- RIP command: redistribute kernel
 -- RIP command: redistribute kernel metric <0-16>
 -- RIP command: redistribute kernel route-map ROUTE-MAP
 -- RIP command: no redistribute kernel
     'redistribute kernel' redistributes routing information from kernel
     route entries into the RIP tables.  'no redistribute kernel'
     disables the routes.

 -- RIP command: redistribute static
 -- RIP command: redistribute static metric <0-16>
 -- RIP command: redistribute static route-map ROUTE-MAP
 -- RIP command: no redistribute static
     'redistribute static' redistributes routing information from static
     route entries into the RIP tables.  'no redistribute static'
     disables the routes.

 -- RIP command: redistribute connected
 -- RIP command: redistribute connected metric <0-16>
 -- RIP command: redistribute connected route-map ROUTE-MAP
 -- RIP command: no redistribute connected
     Redistribute connected routes into the RIP tables.  'no
     redistribute connected' disables the connected routes in the RIP
     tables.  This command redistribute connected of the interface which
     RIP disabled.  The connected route on RIP enabled interface is
     announced by default.

 -- RIP command: redistribute ospf
 -- RIP command: redistribute ospf metric <0-16>
 -- RIP command: redistribute ospf route-map ROUTE-MAP
 -- RIP command: no redistribute ospf
     'redistribute ospf' redistributes routing information from ospf
     route entries into the RIP tables.  'no redistribute ospf' disables
     the routes.

 -- RIP command: redistribute bgp
 -- RIP command: redistribute bgp metric <0-16>
 -- RIP command: redistribute bgp route-map ROUTE-MAP
 -- RIP command: no redistribute bgp
     'redistribute bgp' redistributes routing information from bgp route
     entries into the RIP tables.  'no redistribute bgp' disables the
     routes.

   If you want to specify RIP only static routes:

 -- RIP command: default-information originate

 -- RIP command: route A.B.C.D/M
 -- RIP command: no route A.B.C.D/M
     This command is specific to Quagga.  The 'route' command makes a
     static route only inside RIP. This command should be used only by
     advanced users who are particularly knowledgeable about the RIP
     protocol.  In most cases, we recommend creating a static route in
     Quagga and redistributing it in RIP using 'redistribute static'.

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File: quagga.info,  Node: Filtering RIP Routes,  Next: RIP Metric Manipulation,  Prev: How to Announce RIP route,  Up: RIP

5.5 Filtering RIP Routes
========================

RIP routes can be filtered by a distribute-list.

 -- Command: distribute-list ACCESS_LIST DIRECT IFNAME
     You can apply access lists to the interface with a
     'distribute-list' command.  ACCESS_LIST is the access list name.
     DIRECT is 'in' or 'out'.  If DIRECT is 'in' the access list is
     applied to input packets.

     The 'distribute-list' command can be used to filter the RIP path.
     'distribute-list' can apply access-lists to a chosen interface.
     First, one should specify the access-list.  Next, the name of the
     access-list is used in the distribute-list command.  For example,
     in the following configuration 'eth0' will permit only the paths
     that match the route 10.0.0.0/8

          !
          router rip
           distribute-list private in eth0
          !
          access-list private permit 10 10.0.0.0/8
          access-list private deny any
          !

   'distribute-list' can be applied to both incoming and outgoing data.

 -- Command: distribute-list prefix PREFIX_LIST (in|out) IFNAME
     You can apply prefix lists to the interface with a
     'distribute-list' command.  PREFIX_LIST is the prefix list name.
     Next is the direction of 'in' or 'out'.  If DIRECT is 'in' the
     access list is applied to input packets.

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File: quagga.info,  Node: RIP Metric Manipulation,  Next: RIP distance,  Prev: Filtering RIP Routes,  Up: RIP

5.6 RIP Metric Manipulation
===========================

RIP metric is a value for distance for the network.  Usually 'ripd'
increment the metric when the network information is received.
Redistributed routes' metric is set to 1.

 -- RIP command: default-metric <1-16>
 -- RIP command: no default-metric <1-16>
     This command modifies the default metric value for redistributed
     routes.  The default value is 1.  This command does not affect
     connected route even if it is redistributed by 'redistribute
     connected'.  To modify connected route's metric value, please use
     'redistribute connected metric' or 'route-map'.  'offset-list' also
     affects connected routes.

 -- RIP command: offset-list ACCESS-LIST (in|out)
 -- RIP command: offset-list ACCESS-LIST (in|out) IFNAME

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File: quagga.info,  Node: RIP distance,  Next: RIP route-map,  Prev: RIP Metric Manipulation,  Up: RIP

5.7 RIP distance
================

Distance value is used in zebra daemon.  Default RIP distance is 120.

 -- RIP command: distance <1-255>
 -- RIP command: no distance <1-255>
     Set default RIP distance to specified value.

 -- RIP command: distance <1-255> A.B.C.D/M
 -- RIP command: no distance <1-255> A.B.C.D/M
     Set default RIP distance to specified value when the route's source
     IP address matches the specified prefix.

 -- RIP command: distance <1-255> A.B.C.D/M ACCESS-LIST
 -- RIP command: no distance <1-255> A.B.C.D/M ACCESS-LIST
     Set default RIP distance to specified value when the route's source
     IP address matches the specified prefix and the specified
     access-list.

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File: quagga.info,  Node: RIP route-map,  Next: RIP Authentication,  Prev: RIP distance,  Up: RIP

5.8 RIP route-map
=================

Usage of 'ripd''s route-map support.

   Optional argument route-map MAP_NAME can be added to each
'redistribute' statement.

     redistribute static [route-map MAP_NAME]
     redistribute connected [route-map MAP_NAME]
     .....

   Cisco applies route-map _before_ routes will exported to rip route
table.  In current Quagga's test implementation, 'ripd' applies
route-map after routes are listed in the route table and before routes
will be announced to an interface (something like output filter).  I
think it is not so clear, but it is draft and it may be changed at
future.

   Route-map statement (*note Route Map::) is needed to use route-map
functionality.

 -- Route Map: match interface WORD
     This command match to incoming interface.  Notation of this match
     is different from Cisco.  Cisco uses a list of interfaces - NAME1
     NAME2 ...  NAMEN. Ripd allows only one name (maybe will change in
     the future).  Next - Cisco means interface which includes next-hop
     of routes (it is somewhat similar to "ip next-hop" statement).
     Ripd means interface where this route will be sent.  This
     difference is because "next-hop" of same routes which sends to
     different interfaces must be different.  Maybe it'd be better to
     made new matches - say "match interface-out NAME" or something like
     that.

 -- Route Map: match ip address WORD
 -- Route Map: match ip address prefix-list WORD
     Match if route destination is permitted by access-list.

 -- Route Map: match ip next-hop WORD
 -- Route Map: match ip next-hop prefix-list WORD
     Match if route next-hop (meaning next-hop listed in the rip
     route-table as displayed by "show ip rip") is permitted by
     access-list.

 -- Route Map: match metric <0-4294967295>
     This command match to the metric value of RIP updates.  For other
     protocol compatibility metric range is shown as <0-4294967295>.
     But for RIP protocol only the value range <0-16> make sense.

 -- Route Map: set ip next-hop A.B.C.D
     This command set next hop value in RIPv2 protocol.  This command
     does not affect RIPv1 because there is no next hop field in the
     packet.

 -- Route Map: set metric <0-4294967295>
     Set a metric for matched route when sending announcement.  The
     metric value range is very large for compatibility with other
     protocols.  For RIP, valid metric values are from 1 to 16.

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File: quagga.info,  Node: RIP Authentication,  Next: RIP Timers,  Prev: RIP route-map,  Up: RIP

5.9 RIP Authentication
======================

RIPv2 allows packets to be authenticated via either an insecure plain
text password, included with the packet, or via a more secure MD5 based
HMAC (keyed-Hashing for Message AuthentiCation), RIPv1 can not be
authenticated at all, thus when authentication is configured 'ripd' will
discard routing updates received via RIPv1 packets.

   However, unless RIPv1 reception is disabled entirely, *Note RIP
Version Control::, RIPv1 REQUEST packets which are received, which query
the router for routing information, will still be honoured by 'ripd',
and 'ripd' WILL reply to such packets.  This allows 'ripd' to honour
such REQUESTs (which sometimes is used by old equipment and very simple
devices to bootstrap their default route), while still providing
security for route updates which are received.

   In short: Enabling authentication prevents routes being updated by
unauthenticated remote routers, but still can allow routes (I.e.  the
entire RIP routing table) to be queried remotely, potentially by anyone
on the internet, via RIPv1.

   To prevent such unauthenticated querying of routes disable RIPv1,
*Note RIP Version Control::.

 -- Interface command: ip rip authentication mode md5
 -- Interface command: no ip rip authentication mode md5
     Set the interface with RIPv2 MD5 authentication.

 -- Interface command: ip rip authentication mode text
 -- Interface command: no ip rip authentication mode text
     Set the interface with RIPv2 simple password authentication.

 -- Interface command: ip rip authentication string STRING
 -- Interface command: no ip rip authentication string STRING
     RIP version 2 has simple text authentication.  This command sets
     authentication string.  The string must be shorter than 16
     characters.

 -- Interface command: ip rip authentication key-chain KEY-CHAIN
 -- Interface command: no ip rip authentication key-chain KEY-CHAIN
     Specifiy Keyed MD5 chain.

     !
     key chain test
      key 1
       key-string test
     !
     interface eth1
      ip rip authentication mode md5
      ip rip authentication key-chain test
     !

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File: quagga.info,  Node: RIP Timers,  Next: Show RIP Information,  Prev: RIP Authentication,  Up: RIP

5.10 RIP Timers
===============

 -- RIP command: timers basic UPDATE TIMEOUT GARBAGE

     RIP protocol has several timers.  User can configure those timers'
     values by 'timers basic' command.

     The default settings for the timers are as follows:

        * The update timer is 30 seconds.  Every update timer seconds,
          the RIP process is awakened to send an unsolicited Response
          message containing the complete routing table to all
          neighboring RIP routers.

        * The timeout timer is 180 seconds.  Upon expiration of the
          timeout, the route is no longer valid; however, it is retained
          in the routing table for a short time so that neighbors can be
          notified that the route has been dropped.

        * The garbage collect timer is 120 seconds.  Upon expiration of
          the garbage-collection timer, the route is finally removed
          from the routing table.

     The 'timers basic' command allows the the default values of the
     timers listed above to be changed.

 -- RIP command: no timers basic
     The 'no timers basic' command will reset the timers to the default
     settings listed above.

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File: quagga.info,  Node: Show RIP Information,  Next: RIP Debug Commands,  Prev: RIP Timers,  Up: RIP

5.11 Show RIP Information
=========================

To display RIP routes.

 -- Command: show ip rip
     Show RIP routes.

   The command displays all RIP routes.  For routes that are received
through RIP, this command will display the time the packet was sent and
the tag information.  This command will also display this information
for routes redistributed into RIP.

 -- Command: show ip rip status
     The command displays current RIP status.  It includes RIP timer,
     filtering, version, RIP enabled interface and RIP peer inforation.

     ripd> show ip rip status
     Routing Protocol is "rip"
       Sending updates every 30 seconds with +/-50%, next due in 35 seconds
       Timeout after 180 seconds, garbage collect after 120 seconds
       Outgoing update filter list for all interface is not set
       Incoming update filter list for all interface is not set
       Default redistribution metric is 1
       Redistributing: kernel connected
       Default version control: send version 2, receive version 2
         Interface        Send  Recv
       Routing for Networks:
         eth0
         eth1
         1.1.1.1
         203.181.89.241
       Routing Information Sources:
         Gateway          BadPackets BadRoutes  Distance Last Update

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File: quagga.info,  Node: RIP Debug Commands,  Prev: Show RIP Information,  Up: RIP

5.12 RIP Debug Commands
=======================

Debug for RIP protocol.

 -- Command: debug rip events
     Debug rip events.

   'debug rip' will show RIP events.  Sending and receiving packets,
timers, and changes in interfaces are events shown with 'ripd'.

 -- Command: debug rip packet
     Debug rip packet.

   'debug rip packet' will display detailed information about the RIP
packets.  The origin and port number of the packet as well as a packet
dump is shown.

 -- Command: debug rip zebra
     Debug rip between zebra communication.

   This command will show the communication between 'ripd' and 'zebra'.
The main information will include addition and deletion of paths to the
kernel and the sending and receiving of interface information.

 -- Command: show debugging rip
     Display 'ripd''s debugging option.

   'show debugging rip' will show all information currently set for ripd
debug.

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File: quagga.info,  Node: RIPng,  Next: OSPFv2,  Prev: RIP,  Up: Top

6 RIPng
*******

'ripngd' supports the RIPng protocol as described in RFC2080.  It's an
IPv6 reincarnation of the RIP protocol.

* Menu:

* Invoking ripngd::             
* ripngd Configuration::        
* ripngd Terminal Mode Commands::  
* ripngd Filtering Commands::   

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File: quagga.info,  Node: Invoking ripngd,  Next: ripngd Configuration,  Up: RIPng

6.1 Invoking ripngd
===================

There are no 'ripngd' specific invocation options.  Common options can
be specified (*note Common Invocation Options::).

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File: quagga.info,  Node: ripngd Configuration,  Next: ripngd Terminal Mode Commands,  Prev: Invoking ripngd,  Up: RIPng

6.2 ripngd Configuration
========================

Currently ripngd supports the following commands:

 -- Command: router ripng
     Enable RIPng.

 -- RIPng Command: flush_timer TIME
     Set flush timer.

 -- RIPng Command: network NETWORK
     Set RIPng enabled interface by NETWORK

 -- RIPng Command: network IFNAME
     Set RIPng enabled interface by IFNAME

 -- RIPng Command: route NETWORK
     Set RIPng static routing announcement of NETWORK.

 -- Command: router zebra
     This command is the default and does not appear in the
     configuration.  With this statement, RIPng routes go to the 'zebra'
     daemon.

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File: quagga.info,  Node: ripngd Terminal Mode Commands,  Next: ripngd Filtering Commands,  Prev: ripngd Configuration,  Up: RIPng

6.3 ripngd Terminal Mode Commands
=================================

 -- Command: show ip ripng

 -- Command: show debugging ripng

 -- Command: debug ripng events

 -- Command: debug ripng packet

 -- Command: debug ripng zebra

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File: quagga.info,  Node: ripngd Filtering Commands,  Prev: ripngd Terminal Mode Commands,  Up: RIPng

6.4 ripngd Filtering Commands
=============================

 -- Command: distribute-list ACCESS_LIST (in|out) IFNAME
     You can apply an access-list to the interface using the
     'distribute-list' command.  ACCESS_LIST is an access-list name.
     DIRECT is 'in' or 'out'.  If DIRECT is 'in', the access-list is
     applied only to incoming packets.

          distribute-list local-only out sit1

\1f
File: quagga.info,  Node: OSPFv2,  Next: OSPFv3,  Prev: RIPng,  Up: Top

7 OSPFv2
********

OSPF (Open Shortest Path First) version 2 is a routing protocol which is
described in 'RFC2328, OSPF Version 2'.  OSPF is an IGP (Interior
Gateway Protocol).  Compared with RIP, OSPF can provide scalable network
support and faster convergence times.  OSPF is widely used in large
networks such as ISP (Internet Service Provider) backbone and enterprise
networks.

* Menu:

* OSPF Fundamentals::
* Configuring ospfd::           
* OSPF router::                 
* OSPF area::                   
* OSPF interface::              
* Redistribute routes to OSPF::  
* Showing OSPF information::    
* Opaque LSA::
* OSPF Traffic Engineering::
* Router Information::
* Debugging OSPF::              
* OSPF Configuration Examples::

\1f
File: quagga.info,  Node: OSPF Fundamentals,  Next: Configuring ospfd,  Up: OSPFv2

7.1 OSPF Fundamentals
=====================

OSPF is, mostly, a link-state routing protocol.  In contrast to
"distance-vector" protocols, such as RIP or BGP, where routers describe
available "paths" (i.e.  routes) to each other, in "link-state"
protocols routers instead describe the state of their links to their
immediate neighbouring routers.

   Each router describes their link-state information in a message known
as an LSA (Link State Advertisement), which is then propogated through
to all other routers in a link-state routing domain, by a process called
"flooding".  Each router thus builds up an LSDB (Link State Database) of
all the link-state messages.  From this collection of LSAs in the LSDB,
each router can then calculate the shortest path to any other router,
based on some common metric, by using an algorithm such as Edgser
Dijkstra (http://www.cs.utexas.edu/users/EWD/)'s SPF (Shortest Path
First).

   By describing connectivity of a network in this way, in terms of
routers and links rather than in terms of the paths through a network, a
link-state protocol can use less bandwidth and converge more quickly
than other protocols.  A link-state protocol need distribute only one
link-state message throughout the link-state domain when a link on any
single given router changes state, in order for all routers to
reconverge on the best paths through the network.  In contrast, distance
vector protocols can require a progression of different path update
messages from a series of different routers in order to converge.

   The disadvantage to a link-state protocol is that the process of
computing the best paths can be relatively intensive when compared to
distance-vector protocols, in which near to no computation need be done
other than (potentially) select between multiple routes.  This overhead
is mostly negligible for modern embedded CPUs, even for networks with
thousands of nodes.  The primary scaling overhead lies more in coping
with the ever greater frequency of LSA updates as the size of a
link-state area increases, in managing the LSDB and required flooding.

   This section aims to give a distilled, but accurate, description of
the more important workings of OSPF which an administrator may need to
know to be able best configure and trouble-shoot OSPF.

7.1.1 OSPF Mechanisms
---------------------

OSPF defines a range of mechanisms, concerned with detecting, describing
and propogating state through a network.  These mechanisms will nearly
all be covered in greater detail further on.  They may be broadly
classed as:

"The Hello Protocol"

     The OSPF Hello protocol allows OSPF to quickly detect changes in
     two-way reachability between routers on a link.  OSPF can
     additionally avail of other sources of reachability information,
     such as link-state information provided by hardware, or through
     dedicated reachability protocols such as BFD (Bi-directional
     Forwarding Detection).

     OSPF also uses the Hello protocol to propagate certain state
     between routers sharing a link, for example:

        * Hello protocol configured state, such as the dead-interval.
        * Router priority, for DR/BDR election.
        * DR/BDR election results.
        * Any optional capabilities supported by each router.

     The Hello protocol is comparatively trivial and will not be
     explored in greater detail than here.

"LSAs"

     At the heart of OSPF are LSA (Link State Advertisement) messages.
     Despite the name, some LSAs do not, strictly speaking, describe
     link-state information.  Common LSAs describe information such as:

        * Routers, in terms of their links.
        * Networks, in terms of attached routers.
        * Routes, external to a link-state domain:

             * External Routes

               Routes entirely external to OSPF.  Routers originating
               such routes are known as ASBR (Autonomous-System Border
               Router) routers.

             * Summary Routes

               Routes which summarise routing information relating to
               OSPF areas external to the OSPF link-state area at hand,
               originated by ABR (Area Boundary Router) routers.

"LSA Flooding"
     OSPF defines several related mechanisms, used to manage
     synchronisation of LSDBs between neighbours as neighbours form
     adjacencies and the propogation, or "flooding" of new or updated
     LSAs.

     *Note OSPF Flooding::.

"Areas"
     OSPF provides for the protocol to be broken up into multiple
     smaller and independent link-state areas.  Each area must be
     connected to a common backbone area by an ABR (Area Boundary
     Router).  These ABR routers are responsible for summarising the
     link-state routing information of an area into "Summary LSAs",
     possibly in a condensed (i.e.  aggregated) form, and then
     originating these summaries into all other areas the ABR is
     connected to.

     Note that only summaries and external routes are passed between
     areas.  As these describe _paths_, rather than any router
     link-states, routing between areas hence is by "distance-vector",
     *not* link-state.

     *Note OSPF Areas::.

7.1.2 OSPF LSAs
---------------

LSAs are the core object in OSPF.  Everything else in OSPF revolves
around detecting what to describe in LSAs, when to update them, how to
flood them throughout a network and how to calculate routes from them.

   There are a variety of different LSAs, for purposes such as
describing actual link-state information, describing paths (i.e.
routes), describing bandwidth usage of links for TE (Traffic
Engineering) purposes, and even arbitrary data by way of _Opaque_ LSAs.

7.1.2.1 LSA Header
..................

All LSAs share a common header with the following information:

   * Type

     Different types of LSAs describe different things in OSPF.  Types
     include:

        * Router LSA
        * Network LSA
        * Network Summary LSA
        * Router Summary LSA
        * AS-External LSA

     The specifics of the different types of LSA are examined below.

   * Advertising Router

     The Router ID of the router originating the LSA, see *note ospf
     router-id::.

   * LSA ID

     The ID of the LSA, which is typically derived in some way from the
     information the LSA describes, e.g.  a Router LSA uses the Router
     ID as the LSA ID, a Network LSA will have the IP address of the DR
     as its LSA ID.

     The combination of the Type, ID and Advertising Router ID must
     uniquely identify the LSA.  There can however be multiple instances
     of an LSA with the same Type, LSA ID and Advertising Router ID, see
     *note LSA Sequence Number: OSPF LSA sequence number.

   * Age

     A number to allow stale LSAs to, eventually, be purged by routers
     from their LSDBs.

     The value nominally is one of seconds.  An age of 3600, i.e.  1
     hour, is called the "MaxAge".  MaxAge LSAs are ignored in routing
     calculations.  LSAs must be periodically refreshed by their
     Advertising Router before reaching MaxAge if they are to remain
     valid.

     Routers may deliberately flood LSAs with the age artificially set
     to 3600 to indicate an LSA is no longer valid.  This is called
     "flushing" of an LSA.

     It is not abnormal to see stale LSAs in the LSDB, this can occur
     where a router has shutdown without flushing its LSA(s), e.g.
     where it has become disconnected from the network.  Such LSAs do
     little harm.

   * Sequence Number

     A number used to distinguish newer instances of an LSA from older
     instances.

7.1.2.2 Link-State LSAs
.......................

Of all the various kinds of LSAs, just two types comprise the actual
link-state part of OSPF, Router LSAs and Network LSAs.  These LSA types
are absolutely core to the protocol.

   Instances of these LSAs are specific to the link-state area in which
they are originated.  Routes calculated from these two LSA types are
called "intra-area routes".

   * Router LSA

     Each OSPF Router must originate a router LSA to describe itself.
     In it, the router lists each of its OSPF enabled interfaces, for
     the given link-state area, in terms of:

        * Cost

          The output cost of that interface, scaled inversely to some
          commonly known reference value, *Note auto-cost
          reference-bandwidth: OSPF auto-cost reference-bandwidth.

        * Link Type
             * Transit Network

               A link to a multi-access network, on which the router has
               at least one Full adjacency with another router.

             * PtP (Point-to-Point)

               A link to a single remote router, with a Full adjacency.
               No DR (Designated Router) is elected on such links; no
               network LSA is originated for such a link.

             * Stub

               A link with no adjacent neighbours, or a host route.

        * Link ID and Data

          These values depend on the Link Type:

          Link Type     Link ID                 Link Data
                                                
          --------------------------------------------------------------
          Transit       Link IP address of      Interface IP address
                        the DR                  
          Point-to-PointRouter ID of the        Local interface IP
                        remote router           address, or the
                                                ifindex (MIB-II
                                                interface index) for
                                                unnumbered links
                                                
          Stub          IP address              Subnet Mask
                                                

     Links on a router may be listed multiple times in the Router LSA,
     e.g.  a PtP interface on which OSPF is enabled must _always_ be
     described by a Stub link in the Router LSA, in addition to being
     listed as PtP link in the Router LSA if the adjacency with the
     remote router is Full.

     Stub links may also be used as a way to describe links on which
     OSPF is _not_ spoken, known as "passive interfaces", see *note
     passive-interface: OSPF passive-interface.

   * Network LSA

     On multi-access links (e.g.  ethernets, certain kinds of ATM and
     X.25 configurations), routers elect a DR.  The DR is responsible
     for originating a Network LSA, which helps reduce the information
     needed to describe multi-access networks with multiple routers
     attached.  The DR also acts as a hub for the flooding of LSAs on
     that link, thus reducing flooding overheads.

     The contents of the Network LSA describes the:

        * Subnet Mask

          As the LSA ID of a Network LSA must be the IP address of the
          DR, the Subnet Mask together with the LSA ID gives you the
          network address.

        * Attached Routers

          Each router fully-adjacent with the DR is listed in the LSA,
          by their Router-ID. This allows the corresponding Router LSAs
          to be easily retrieved from the LSDB.

   Summary of Link State LSAs:

LSA Type      LSA ID Describes        LSA Data Describes
                                      
--------------------------------------------------------------------
Router LSA    The Router ID           The OSPF enabled links of
                                      the router, within a
                                      specific link-state area.
                                      
Network LSA   The IP address of the   The Subnet Mask of the
              DR for the network      network, and the Router IDs
                                      of all routers on the
                                      network.

   With an LSDB composed of just these two types of LSA, it is possible
to construct a directed graph of the connectivity between all routers
and networks in a given OSPF link-state area.  So, not surprisingly,
when OSPF routers build updated routing tables, the first stage of SPF
calculation concerns itself only with these two LSA types.

7.1.2.3 Link-State LSA Examples
...............................

The example below (*note OSPF Link-State LSA Example::) shows two LSAs,
both originated by the same router (Router ID 192.168.0.49) and with the
same LSA ID (192.168.0.49), but of different LSA types.

   The first LSA being the router LSA describing 192.168.0.49's links: 2
links to multi-access networks with fully-adjacent neighbours (i.e.
Transit links) and 1 being a Stub link (no adjacent neighbours).

   The second LSA being a Network LSA, for which 192.168.0.49 is the DR,
listing the Router IDs of 4 routers on that network which are fully
adjacent with 192.168.0.49.

     # show ip ospf database router 192.168.0.49

            OSPF Router with ID (192.168.0.53)


                     Router Link States (Area 0.0.0.0)

       LS age: 38
       Options: 0x2  : *|-|-|-|-|-|E|*
       LS Flags: 0x6
       Flags: 0x2 : ASBR
       LS Type: router-LSA
       Link State ID: 192.168.0.49
       Advertising Router: 192.168.0.49
       LS Seq Number: 80000f90
       Checksum: 0x518b
       Length: 60
        Number of Links: 3

         Link connected to: a Transit Network
          (Link ID) Designated Router address: 192.168.1.3
          (Link Data) Router Interface address: 192.168.1.3
           Number of TOS metrics: 0
            TOS 0 Metric: 10

         Link connected to: a Transit Network
          (Link ID) Designated Router address: 192.168.0.49
          (Link Data) Router Interface address: 192.168.0.49
           Number of TOS metrics: 0
            TOS 0 Metric: 10

         Link connected to: Stub Network
          (Link ID) Net: 192.168.3.190
          (Link Data) Network Mask: 255.255.255.255
           Number of TOS metrics: 0
            TOS 0 Metric: 39063
     # show ip ospf database network 192.168.0.49

            OSPF Router with ID (192.168.0.53)


                     Net Link States (Area 0.0.0.0)

       LS age: 285
       Options: 0x2  : *|-|-|-|-|-|E|*
       LS Flags: 0x6
       LS Type: network-LSA
       Link State ID: 192.168.0.49 (address of Designated Router)
       Advertising Router: 192.168.0.49
       LS Seq Number: 80000074
       Checksum: 0x0103
       Length: 40
       Network Mask: /29
             Attached Router: 192.168.0.49
             Attached Router: 192.168.0.52
             Attached Router: 192.168.0.53
             Attached Router: 192.168.0.54

   Note that from one LSA, you can find the other.  E.g.  Given the
Network-LSA you have a list of Router IDs on that network, from which
you can then look up, in the local LSDB, the matching Router LSA.  From
that Router-LSA you may (potentially) find links to other Transit
networks and Routers IDs which can be used to lookup the corresponding
Router or Network LSA.  And in that fashion, one can find all the
Routers and Networks reachable from that starting LSA.

   Given the Router LSA instead, you have the IP address of the DR of
any attached transit links.  Network LSAs will have that IP as their LSA
ID, so you can then look up that Network LSA and from that find all the
attached routers on that link, leading potentially to more links and
Network and Router LSAs, etc.  etc.

   From just the above two LSAs, one can already see the following
partial topology:


        --------------------- Network: ......
                 |            Designated Router IP: 192.168.1.3
                 |
           IP: 192.168.1.3
            (transit link)
             (cost: 10)
        Router ID: 192.168.0.49(stub)---------- IP: 192.168.3.190/32
             (cost: 10)        (cost: 39063)
            (transit link)
           IP: 192.168.0.49
                 |
                 |
     ------------------------------ Network: 192.168.0.48/29
       |        |           |       Designated Router IP: 192.168.0.49
       |        |           |
       |        |     Router ID: 192.168.0.54
       |        |
       |   Router ID: 192.168.0.53
       |
     Router ID: 192.168.0.52

   Note the Router IDs, though they look like IP addresses and often are
IP addresses, are not strictly speaking IP addresses, nor need they be
reachable addresses (though, OSPF will calculate routes to Router IDs).

7.1.2.4 External LSAs
.....................

External, or "Type 5", LSAs describe routing information which is
entirely external to OSPF, and is "injected" into OSPF.  Such routing
information may have come from another routing protocol, such as RIP or
BGP, they may represent static routes or they may represent a default
route.

   An OSPF router which originates External LSAs is known as an ASBR (AS
Boundary Router).  Unlike the link-state LSAs, and most other LSAs,
which are flooded only within the area in which they originate, External
LSAs are flooded through-out the OSPF network to all areas capable of
carrying External LSAs (*note OSPF Areas::).

   Routes internal to OSPF (intra-area or inter-area) are always
preferred over external routes.

   The External LSA describes the following:

   * IP Network number

     The IP Network number of the route is described by the LSA ID
     field.

   * IP Network Mask

     The body of the External LSA describes the IP Network Mask of the
     route.  This, together with the LSA ID, describes the prefix of the
     IP route concerned.

   * Metric

     The cost of the External Route.  This cost may be an OSPF cost
     (also known as a "Type 1" metric), i.e.  equivalent to the normal
     OSPF costs, or an externally derived cost ("Type 2" metric) which
     is not comparable to OSPF costs and always considered larger than
     any OSPF cost.  Where there are both Type 1 and 2 External routes
     for a route, the Type 1 is always preferred.

   * Forwarding Address

     The address of the router to forward packets to for the route.
     This may be, and usually is, left as 0 to specify that the ASBR
     originating the External LSA should be used.  There must be an
     internal OSPF route to the forwarding address, for the forwarding
     address to be useable.

   * Tag

     An arbitrary 4-bytes of data, not interpreted by OSPF, which may
     carry whatever information about the route which OSPF speakers
     desire.

7.1.2.5 AS External LSA Example
...............................

To illustrate, below is an example of an External LSA in the LSDB of an
OSPF router.  It describes a route to the IP prefix of 192.168.165.0/24,
originated by the ASBR with Router-ID 192.168.0.49.  The metric of 20 is
external to OSPF. The forwarding address is 0, so the route should
forward to the originating ASBR if selected.

     # show ip ospf database external 192.168.165.0
       LS age: 995
       Options: 0x2  : *|-|-|-|-|-|E|*
       LS Flags: 0x9
       LS Type: AS-external-LSA
       Link State ID: 192.168.165.0 (External Network Number)
       Advertising Router: 192.168.0.49
       LS Seq Number: 800001d8
       Checksum: 0xea27
       Length: 36
       Network Mask: /24
             Metric Type: 2 (Larger than any link state path)
             TOS: 0
             Metric: 20
             Forward Address: 0.0.0.0
             External Route Tag: 0

   We can add this to our partial topology from above, which now looks
like:
        --------------------- Network: ......
                 |            Designated Router IP: 192.168.1.3
                 |
           IP: 192.168.1.3      /---- External route: 192.168.165.0/24
            (transit link)     /                Cost: 20 (External metric)
             (cost: 10)       /
        Router ID: 192.168.0.49(stub)---------- IP: 192.168.3.190/32
             (cost: 10)        (cost: 39063)
            (transit link)
           IP: 192.168.0.49
                 |
                 |
     ------------------------------ Network: 192.168.0.48/29
       |        |           |       Designated Router IP: 192.168.0.49
       |        |           |
       |        |     Router ID: 192.168.0.54
       |        |
       |   Router ID: 192.168.0.53
       |
     Router ID: 192.168.0.52

7.1.2.6 Summary LSAs
....................

Summary LSAs are created by ABRs to summarise the destinations available
within one area to other areas.  These LSAs may describe IP networks,
potentially in aggregated form, or ASBR routers.

7.1.3 OSPF Flooding
-------------------

7.1.4 OSPF Areas
----------------

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File: quagga.info,  Node: Configuring ospfd,  Next: OSPF router,  Prev: OSPF Fundamentals,  Up: OSPFv2

7.2 Configuring ospfd
=====================

There are no 'ospfd' specific options.  Common options can be specified
(*note Common Invocation Options::) to 'ospfd'.  'ospfd' needs to
acquire interface information from 'zebra' in order to function.
Therefore 'zebra' must be running before invoking 'ospfd'.  Also, if
'zebra' is restarted then 'ospfd' must be too.

   Like other daemons, 'ospfd' configuration is done in OSPF specific
configuration file 'ospfd.conf'.

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File: quagga.info,  Node: OSPF router,  Next: OSPF area,  Prev: Configuring ospfd,  Up: OSPFv2

7.3 OSPF router
===============

To start OSPF process you have to specify the OSPF router.  As of this
writing, 'ospfd' does not support multiple OSPF processes.

 -- Command: router ospf
 -- Command: no router ospf
     Enable or disable the OSPF process.  'ospfd' does not yet support
     multiple OSPF processes.  So you can not specify an OSPF process
     number.

 -- OSPF Command: ospf router-id A.B.C.D
 -- OSPF Command: no ospf router-id
     This sets the router-ID of the OSPF process.  The router-ID may be
     an IP address of the router, but need not be - it can be any
     arbitrary 32bit number.  However it MUST be unique within the
     entire OSPF domain to the OSPF speaker - bad things will happen if
     multiple OSPF speakers are configured with the same router-ID! If
     one is not specified then 'ospfd' will obtain a router-ID
     automatically from 'zebra'.

 -- OSPF Command: ospf abr-type TYPE
 -- OSPF Command: no ospf abr-type TYPE
     TYPE can be cisco|ibm|shortcut|standard.  The "Cisco" and "IBM"
     types are equivalent.

     The OSPF standard for ABR behaviour does not allow an ABR to
     consider routes through non-backbone areas when its links to the
     backbone are down, even when there are other ABRs in attached
     non-backbone areas which still can reach the backbone - this
     restriction exists primarily to ensure routing-loops are avoided.

     With the "Cisco" or "IBM" ABR type, the default in this release of
     Quagga, this restriction is lifted, allowing an ABR to consider
     summaries learnt from other ABRs through non-backbone areas, and
     hence route via non-backbone areas as a last resort when, and only
     when, backbone links are down.

     Note that areas with fully-adjacent virtual-links are considered to
     be "transit capable" and can always be used to route backbone
     traffic, and hence are unaffected by this setting (*note OSPF
     virtual-link::).

     More information regarding the behaviour controlled by this command
     can be found in 'RFC 3509, Alternative Implementations of OSPF Area
     Border Routers', and 'draft-ietf-ospf-shortcut-abr-02.txt'.

     Quote: "Though the definition of the ABR (Area Border Router) in
     the OSPF specification does not require a router with multiple
     attached areas to have a backbone connection, it is actually
     necessary to provide successful routing to the inter-area and
     external destinations.  If this requirement is not met, all traffic
     destined for the areas not connected to such an ABR or out of the
     OSPF domain, is dropped.  This document describes alternative ABR
     behaviors implemented in Cisco and IBM routers."

 -- OSPF Command: ospf rfc1583compatibility
 -- OSPF Command: no ospf rfc1583compatibility
     'RFC2328', the sucessor to 'RFC1583', suggests according to section
     G.2 (changes) in section 16.4 a change to the path preference
     algorithm that prevents possible routing loops that were possible
     in the old version of OSPFv2.  More specifically it demands that
     inter-area paths and intra-area backbone path are now of equal
     preference but still both preferred to external paths.

     This command should NOT be set normally.

 -- OSPF Command: log-adjacency-changes [detail]
 -- OSPF Command: no log-adjacency-changes [detail]
     Configures ospfd to log changes in adjacency.  With the optional
     detail argument, all changes in adjacency status are shown.
     Without detail, only changes to full or regressions are shown.

 -- OSPF Command: passive-interface INTERFACE
 -- OSPF Command: no passive-interface INTERFACE
     Do not speak OSPF interface on the given interface, but do
     advertise the interface as a stub link in the router-LSA (Link
     State Advertisement) for this router.  This allows one to advertise
     addresses on such connected interfaces without having to originate
     AS-External/Type-5 LSAs (which have global flooding scope) - as
     would occur if connected addresses were redistributed into OSPF
     (*note Redistribute routes to OSPF::).  This is the only way to
     advertise non-OSPF links into stub areas.

 -- OSPF Command: timers throttle spf DELAY INITIAL-HOLDTIME
          MAX-HOLDTIME
 -- OSPF Command: no timers throttle spf
     This command sets the initial DELAY, the INITIAL-HOLDTIME and the
     MAXIMUM-HOLDTIME between when SPF is calculated and the event which
     triggered the calculation.  The times are specified in milliseconds
     and must be in the range of 0 to 600000 milliseconds.

     The DELAY specifies the minimum amount of time to delay SPF
     calculation (hence it affects how long SPF calculation is delayed
     after an event which occurs outside of the holdtime of any previous
     SPF calculation, and also serves as a minimum holdtime).

     Consecutive SPF calculations will always be seperated by at least
     'hold-time' milliseconds.  The hold-time is adaptive and initially
     is set to the INITIAL-HOLDTIME configured with the above command.
     Events which occur within the holdtime of the previous SPF
     calculation will cause the holdtime to be increased by
     INITIAL-HOLDTIME, bounded by the MAXIMUM-HOLDTIME configured with
     this command.  If the adaptive hold-time elapses without any
     SPF-triggering event occuring then the current holdtime is reset to
     the INITIAL-HOLDTIME.  The current holdtime can be viewed with
     *note show ip ospf::, where it is expressed as a multiplier of the
     INITIAL-HOLDTIME.

          router ospf
           timers throttle spf 200 400 10000

     In this example, the DELAY is set to 200ms, the INITIAL HOLDTIME is
     set to 400ms and the MAXIMUM HOLDTIME to 10s.  Hence there will
     always be at least 200ms between an event which requires SPF
     calculation and the actual SPF calculation.  Further consecutive
     SPF calculations will always be seperated by between 400ms to 10s,
     the hold-time increasing by 400ms each time an SPF-triggering event
     occurs within the hold-time of the previous SPF calculation.

     This command supercedes the 'timers spf' command in previous Quagga
     releases.

 -- OSPF Command: max-metric router-lsa [on-startup|on-shutdown]
          <5-86400>
 -- OSPF Command: max-metric router-lsa administrative
 -- OSPF Command: no max-metric router-lsa
          [on-startup|on-shutdown|administrative]
     This enables 'RFC3137, OSPF Stub Router Advertisement' support,
     where the OSPF process describes its transit links in its
     router-LSA as having infinite distance so that other routers will
     avoid calculating transit paths through the router while still
     being able to reach networks through the router.

     This support may be enabled administratively (and indefinitely) or
     conditionally.  Conditional enabling of max-metric router-lsas can
     be for a period of seconds after startup and/or for a period of
     seconds prior to shutdown.

     Enabling this for a period after startup allows OSPF to converge
     fully first without affecting any existing routes used by other
     routers, while still allowing any connected stub links and/or
     redistributed routes to be reachable.  Enabling this for a period
     of time in advance of shutdown allows the router to gracefully
     excuse itself from the OSPF domain.

     Enabling this feature administratively allows for administrative
     intervention for whatever reason, for an indefinite period of time.
     Note that if the configuration is written to file, this
     administrative form of the stub-router command will also be written
     to file.  If 'ospfd' is restarted later, the command will then take
     effect until manually deconfigured.

     Configured state of this feature as well as current status, such as
     the number of second remaining till on-startup or on-shutdown ends,
     can be viewed with the *note show ip ospf:: command.

 -- OSPF Command: auto-cost reference-bandwidth <1-4294967>
 -- OSPF Command: no auto-cost reference-bandwidth
     This sets the reference bandwidth for cost calculations, where this
     bandwidth is considered equivalent to an OSPF cost of 1, specified
     in Mbits/s.  The default is 100Mbit/s (i.e.  a link of bandwidth
     100Mbit/s or higher will have a cost of 1.  Cost of lower bandwidth
     links will be scaled with reference to this cost).

     This configuration setting MUST be consistent across all routers
     within the OSPF domain.

 -- OSPF Command: network A.B.C.D/M area A.B.C.D
 -- OSPF Command: network A.B.C.D/M area <0-4294967295>
 -- OSPF Command: no network A.B.C.D/M area A.B.C.D
 -- OSPF Command: no network A.B.C.D/M area <0-4294967295>
     This command specifies the OSPF enabled interface(s).  If the
     interface has an address from range 192.168.1.0/24 then the command
     below enables ospf on this interface so router can provide network
     information to the other ospf routers via this interface.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0

     Prefix length in interface must be equal or bigger (ie.  smaller
     network) than prefix length in network statement.  For example
     statement above doesn't enable ospf on interface with address
     192.168.1.1/23, but it does on interface with address
     192.168.1.129/25.

     Note that the behavior when there is a peer address defined on an
     interface changed after release 0.99.7.  Currently, if a peer
     prefix has been configured, then we test whether the prefix in the
     network command contains the destination prefix.  Otherwise, we
     test whether the network command prefix contains the local address
     prefix of the interface.

     In some cases it may be more convenient to enable OSPF on a per
     interface/subnet basis (*note OSPF ip ospf area command::).

\1f
File: quagga.info,  Node: OSPF area,  Next: OSPF interface,  Prev: OSPF router,  Up: OSPFv2

7.4 OSPF area
=============

 -- OSPF Command: area A.B.C.D range A.B.C.D/M
 -- OSPF Command: area <0-4294967295> range A.B.C.D/M
 -- OSPF Command: no area A.B.C.D range A.B.C.D/M
 -- OSPF Command: no area <0-4294967295> range A.B.C.D/M
     Summarize intra area paths from specified area into one Type-3
     summary-LSA announced to other areas.  This command can be used
     only in ABR and ONLY router-LSAs (Type-1) and network-LSAs (Type-2)
     (ie.  LSAs with scope area) can be summarized.  Type-5
     AS-external-LSAs can't be summarized - their scope is AS.
     Summarizing Type-7 AS-external-LSAs isn't supported yet by Quagga.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 range 10.0.0.0/8

     With configuration above one Type-3 Summary-LSA with routing info
     10.0.0.0/8 is announced into backbone area if area 0.0.0.10
     contains at least one intra-area network (ie.  described with
     router or network LSA) from this range.

 -- OSPF Command: area A.B.C.D range IPV4_PREFIX not-advertise
 -- OSPF Command: no area A.B.C.D range IPV4_PREFIX not-advertise
     Instead of summarizing intra area paths filter them - ie.  intra
     area paths from this range are not advertised into other areas.
     This command makes sense in ABR only.

 -- OSPF Command: area A.B.C.D range IPV4_PREFIX substitute IPV4_PREFIX
 -- OSPF Command: no area A.B.C.D range IPV4_PREFIX substitute
          IPV4_PREFIX
     Substitute summarized prefix with another prefix.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 range 10.0.0.0/8 substitute 11.0.0.0/8

     One Type-3 summary-LSA with routing info 11.0.0.0/8 is announced
     into backbone area if area 0.0.0.10 contains at least one
     intra-area network (ie.  described with router-LSA or network-LSA)
     from range 10.0.0.0/8.  This command makes sense in ABR only.

 -- OSPF Command: area A.B.C.D virtual-link A.B.C.D
 -- OSPF Command: area <0-4294967295> virtual-link A.B.C.D
 -- OSPF Command: no area A.B.C.D virtual-link A.B.C.D
 -- OSPF Command: no area <0-4294967295> virtual-link A.B.C.D

 -- OSPF Command: area A.B.C.D shortcut
 -- OSPF Command: area <0-4294967295> shortcut
 -- OSPF Command: no area A.B.C.D shortcut
 -- OSPF Command: no area <0-4294967295> shortcut
     Configure the area as Shortcut capable.  See 'RFC3509'.  This
     requires that the 'abr-type' be set to 'shortcut'.

 -- OSPF Command: area A.B.C.D stub
 -- OSPF Command: area <0-4294967295> stub
 -- OSPF Command: no area A.B.C.D stub
 -- OSPF Command: no area <0-4294967295> stub
     Configure the area to be a stub area.  That is, an area where no
     router originates routes external to OSPF and hence an area where
     all external routes are via the ABR(s).  Hence, ABRs for such an
     area do not need to pass AS-External LSAs (type-5s) or ASBR-Summary
     LSAs (type-4) into the area.  They need only pass Network-Summary
     (type-3) LSAs into such an area, along with a default-route
     summary.

 -- OSPF Command: area A.B.C.D stub no-summary
 -- OSPF Command: area <0-4294967295> stub no-summary
 -- OSPF Command: no area A.B.C.D stub no-summary
 -- OSPF Command: no area <0-4294967295> stub no-summary
     Prevents an 'ospfd' ABR from injecting inter-area summaries into
     the specified stub area.

 -- OSPF Command: area A.B.C.D default-cost <0-16777215>
 -- OSPF Command: no area A.B.C.D default-cost <0-16777215>
     Set the cost of default-summary LSAs announced to stubby areas.

 -- OSPF Command: area A.B.C.D export-list NAME
 -- OSPF Command: area <0-4294967295> export-list NAME
 -- OSPF Command: no area A.B.C.D export-list NAME
 -- OSPF Command: no area <0-4294967295> export-list NAME
     Filter Type-3 summary-LSAs announced to other areas originated from
     intra- area paths from specified area.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 export-list foo
          !
          access-list foo permit 10.10.0.0/16
          access-list foo deny any

     With example above any intra-area paths from area 0.0.0.10 and from
     range 10.10.0.0/16 (for example 10.10.1.0/24 and 10.10.2.128/30)
     are announced into other areas as Type-3 summary-LSA's, but any
     others (for example 10.11.0.0/16 or 10.128.30.16/30) aren't.

     This command is only relevant if the router is an ABR for the
     specified area.

 -- OSPF Command: area A.B.C.D import-list NAME
 -- OSPF Command: area <0-4294967295> import-list NAME
 -- OSPF Command: no area A.B.C.D import-list NAME
 -- OSPF Command: no area <0-4294967295> import-list NAME
     Same as export-list, but it applies to paths announced into
     specified area as Type-3 summary-LSAs.

 -- OSPF Command: area A.B.C.D filter-list prefix NAME in
 -- OSPF Command: area A.B.C.D filter-list prefix NAME out
 -- OSPF Command: area <0-4294967295> filter-list prefix NAME in
 -- OSPF Command: area <0-4294967295> filter-list prefix NAME out
 -- OSPF Command: no area A.B.C.D filter-list prefix NAME in
 -- OSPF Command: no area A.B.C.D filter-list prefix NAME out
 -- OSPF Command: no area <0-4294967295> filter-list prefix NAME in
 -- OSPF Command: no area <0-4294967295> filter-list prefix NAME out
     Filtering Type-3 summary-LSAs to/from area using prefix lists.
     This command makes sense in ABR only.

 -- OSPF Command: area A.B.C.D authentication
 -- OSPF Command: area <0-4294967295> authentication
 -- OSPF Command: no area A.B.C.D authentication
 -- OSPF Command: no area <0-4294967295> authentication
     Specify that simple password authentication should be used for the
     given area.

 -- OSPF Command: area A.B.C.D authentication message-digest
 -- OSPF Command: area <0-4294967295> authentication message-digest

     Specify that OSPF packets must be authenticated with MD5 HMACs
     within the given area.  Keying material must also be configured on
     a per-interface basis (*note ip ospf message-digest-key::).

     MD5 authentication may also be configured on a per-interface basis
     (*note ip ospf authentication message-digest::).  Such
     per-interface settings will override any per-area authentication
     setting.

\1f
File: quagga.info,  Node: OSPF interface,  Next: Redistribute routes to OSPF,  Prev: OSPF area,  Up: OSPFv2

7.5 OSPF interface
==================

 -- Interface Command: ip ospf area AREA [ADDR]
 -- Interface Command: no ip ospf area [ADDR]

     Enable OSPF on the interface, optionally restricted to just the IP
     address given by ADDR, putting it in the AREA area.  Per interface
     area settings take precedence to network commands (*note OSPF
     network command::).

     If you have a lot of interfaces, and/or a lot of subnets, then
     enabling OSPF via this command may result in a slight performance
     improvement.

 -- Interface Command: ip ospf authentication-key AUTH_KEY
 -- Interface Command: no ip ospf authentication-key
     Set OSPF authentication key to a simple password.  After setting
     AUTH_KEY, all OSPF packets are authenticated.  AUTH_KEY has length
     up to 8 chars.

     Simple text password authentication is insecure and deprecated in
     favour of MD5 HMAC authentication (*note ip ospf authentication
     message-digest::).

 -- Interface Command: ip ospf authentication message-digest
     Specify that MD5 HMAC authentication must be used on this
     interface.  MD5 keying material must also be configured (*note ip
     ospf message-digest-key::).  Overrides any authentication enabled
     on a per-area basis (*note area authentication message-digest::).

     Note that OSPF MD5 authentication requires that time never go
     backwards (correct time is NOT important, only that it never goes
     backwards), even across resets, if ospfd is to be able to promptly
     reestabish adjacencies with its neighbours after restarts/reboots.
     The host should have system time be set at boot from an external or
     non-volatile source (eg battery backed clock, NTP, etc.)  or else
     the system clock should be periodically saved to non-volative
     storage and restored at boot if MD5 authentication is to be
     expected to work reliably.

 -- Interface Command: ip ospf message-digest-key KEYID md5 KEY
 -- Interface Command: no ip ospf message-digest-key
     Set OSPF authentication key to a cryptographic password.  The
     cryptographic algorithm is MD5.

     KEYID identifies secret key used to create the message digest.
     This ID is part of the protocol and must be consistent across
     routers on a link.

     KEY is the actual message digest key, of up to 16 chars (larger
     strings will be truncated), and is associated with the given KEYID.

 -- Interface Command: ip ospf cost <1-65535>
 -- Interface Command: no ip ospf cost
     Set link cost for the specified interface.  The cost value is set
     to router-LSA's metric field and used for SPF calculation.

 -- Interface Command: ip ospf dead-interval <1-65535>
 -- Interface Command: ip ospf dead-interval minimal hello-multiplier
          <2-20>
 -- Interface Command: no ip ospf dead-interval
     Set number of seconds for RouterDeadInterval timer value used for
     Wait Timer and Inactivity Timer.  This value must be the same for
     all routers attached to a common network.  The default value is 40
     seconds.

     If 'minimal' is specified instead, then the dead-interval is set to
     1 second and one must specify a hello-multiplier.  The
     hello-multiplier specifies how many Hellos to send per second, from
     2 (every 500ms) to 20 (every 50ms).  Thus one can have 1s
     convergence time for OSPF. If this form is specified, then the
     hello-interval advertised in Hello packets is set to 0 and the
     hello-interval on received Hello packets is not checked, thus the
     hello-multiplier need NOT be the same across multiple routers on a
     common link.

 -- Interface Command: ip ospf hello-interval <1-65535>
 -- Interface Command: no ip ospf hello-interval
     Set number of seconds for HelloInterval timer value.  Setting this
     value, Hello packet will be sent every timer value seconds on the
     specified interface.  This value must be the same for all routers
     attached to a common network.  The default value is 10 seconds.

     This command has no effect if *note ip ospf dead-interval minimal::
     is also specified for the interface.

 -- Interface Command: ip ospf network
          (broadcast|non-broadcast|point-to-multipoint|point-to-point)
 -- Interface Command: no ip ospf network
     Set explicitly network type for specifed interface.

 -- Interface Command: ip ospf priority <0-255>
 -- Interface Command: no ip ospf priority
     Set RouterPriority integer value.  The router with the highest
     priority will be more eligible to become Designated Router.
     Setting the value to 0, makes the router ineligible to become
     Designated Router.  The default value is 1.

 -- Interface Command: ip ospf retransmit-interval <1-65535>
 -- Interface Command: no ip ospf retransmit interval
     Set number of seconds for RxmtInterval timer value.  This value is
     used when retransmitting Database Description and Link State
     Request packets.  The default value is 5 seconds.

 -- Interface Command: ip ospf transmit-delay
 -- Interface Command: no ip ospf transmit-delay
     Set number of seconds for InfTransDelay value.  LSAs' age should be
     incremented by this value when transmitting.  The default value is
     1 seconds.

\1f
File: quagga.info,  Node: Redistribute routes to OSPF,  Next: Showing OSPF information,  Prev: OSPF interface,  Up: OSPFv2

7.6 Redistribute routes to OSPF
===============================

 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
          ROUTE-MAP
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
          metric-type (1|2)
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
          metric-type (1|2) route-map WORD
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric
          <0-16777214>
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric
          <0-16777214> route-map WORD
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
          metric-type (1|2) metric <0-16777214>
 -- OSPF Command: redistribute (kernel|connected|static|rip|bgp)
          metric-type (1|2) metric <0-16777214> route-map WORD
 -- OSPF Command: no redistribute (kernel|connected|static|rip|bgp)
     Redistribute routes of the specified protocol or kind into OSPF,
     with the metric type and metric set if specified, filtering the
     routes using the given route-map if specified.  Redistributed
     routes may also be filtered with distribute-lists, see *note ospf
     distribute-list::.

     Redistributed routes are distributed as into OSPF as Type-5
     External LSAs into links to areas that accept external routes,
     Type-7 External LSAs for NSSA areas and are not redistributed at
     all into Stub areas, where external routes are not permitted.

     Note that for connected routes, one may instead use
     "passive-interface", see *note OSPF passive-interface::.

 -- OSPF Command: default-information originate
 -- OSPF Command: default-information originate metric <0-16777214>
 -- OSPF Command: default-information originate metric <0-16777214>
          metric-type (1|2)
 -- OSPF Command: default-information originate metric <0-16777214>
          metric-type (1|2) route-map WORD
 -- OSPF Command: default-information originate always
 -- OSPF Command: default-information originate always metric
          <0-16777214>
 -- OSPF Command: default-information originate always metric
          <0-16777214> metric-type (1|2)
 -- OSPF Command: default-information originate always metric
          <0-16777214> metric-type (1|2) route-map WORD
 -- OSPF Command: no default-information originate
     Originate an AS-External (type-5) LSA describing a default route
     into all external-routing capable areas, of the specified metric
     and metric type.  If the 'always' keyword is given then the default
     is always advertised, even when there is no default present in the
     routing table.

 -- OSPF Command: distribute-list NAME out
          (kernel|connected|static|rip|ospf
 -- OSPF Command: no distribute-list NAME out
          (kernel|connected|static|rip|ospf
     Apply the access-list filter, NAME, to redistributed routes of the
     given type before allowing the routes to redistributed into OSPF
     (*note OSPF redistribute::).

 -- OSPF Command: default-metric <0-16777214>
 -- OSPF Command: no default-metric

 -- OSPF Command: distance <1-255>
 -- OSPF Command: no distance <1-255>

 -- OSPF Command: distance ospf (intra-area|inter-area|external) <1-255>
 -- OSPF Command: no distance ospf

\1f
File: quagga.info,  Node: Showing OSPF information,  Next: Opaque LSA,  Prev: Redistribute routes to OSPF,  Up: OSPFv2

7.7 Showing OSPF information
============================

 -- Command: show ip ospf
     Show information on a variety of general OSPF and area state and
     configuration information.

 -- Command: show ip ospf interface [INTERFACE]
     Show state and configuration of OSPF the specified interface, or
     all interfaces if no interface is given.

 -- Command: show ip ospf neighbor
 -- Command: show ip ospf neighbor INTERFACE
 -- Command: show ip ospf neighbor detail
 -- Command: show ip ospf neighbor INTERFACE detail

 -- Command: show ip ospf database
 -- Command: show ip ospf database asbr-summary
 -- Command: show ip ospf database external
 -- Command: show ip ospf database network
 -- Command: show ip ospf database asbr-router
 -- Command: show ip ospf database summary
 -- Command: show ip ospf database ... LINK-STATE-ID
 -- Command: show ip ospf database ... LINK-STATE-ID adv-router
          ADV-ROUTER
 -- Command: show ip ospf database ... adv-router ADV-ROUTER
 -- Command: show ip ospf database ... LINK-STATE-ID self-originate
 -- Command: show ip ospf database ... self-originate

 -- Command: show ip ospf database max-age

 -- Command: show ip ospf database self-originate

 -- Command: show ip ospf route
     Show the OSPF routing table, as determined by the most recent SPF
     calculation.

\1f
File: quagga.info,  Node: Opaque LSA,  Next: OSPF Traffic Engineering,  Prev: Showing OSPF information,  Up: OSPFv2

7.8 Opaque LSA
==============

 -- OSPF Command: ospf opaque-lsa
 -- OSPF Command: capability opaque
 -- OSPF Command: no ospf opaque-lsa
 -- OSPF Command: no capability opaque
     'ospfd' support Opaque LSA (RFC2370) as fondment for MPLS Traffic
     Engineering LSA. Prior to used MPLS TE, opaque-lsa must be enable
     in the configuration file.  Alternate command could be "mpls-te on"
     (*note OSPF Traffic Engineering::).

 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external)
 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external) LINK-STATE-ID
 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external) LINK-STATE-ID
          adv-router ADV-ROUTER
 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external) adv-router
          ADV-ROUTER
 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external) LINK-STATE-ID
          self-originate
 -- Command: show ip ospf database
          (opaque-link|opaque-area|opaque-external) self-originate
     Show Opaque LSA from the database.

\1f
File: quagga.info,  Node: OSPF Traffic Engineering,  Next: Router Information,  Prev: Opaque LSA,  Up: OSPFv2

7.9 Traffic Engineering
=======================

 -- OSPF Command: mpls-te on
 -- OSPF Command: no mpls-te
     Enable Traffic Engineering LSA flooding.

 -- OSPF Command: mpls-te router-address <A.B.C.D>
 -- OSPF Command: no mpls-te
     Configure stable IP address for MPLS-TE. This IP address is then
     advertise in Opaque LSA Type-10 TLV=1 (TE) option 1
     (Router-Address).

 -- OSPF Command: mpls-te inter-as area <area-id>|as
 -- OSPF Command: no mpls-te inter-as
     Enable RFC5392 suuport - Inter-AS TE v2 - to flood Traffic
     Engineering parameters of Inter-AS link.  2 modes are supported:
     AREA and AS; LSA are flood in AREA <area-id> with Opaque Type-10,
     respectively in AS with Opaque Type-11.  In all case, Opaque-LSA
     TLV=6.

 -- Command: show ip ospf mpls-te interface
 -- Command: show ip ospf mpls-te interface INTERFACE
     Show MPLS Traffic Engineering parameters for all or specified
     interface.

 -- Command: show ip ospf mpls-te router
     Show Traffic Engineering router parameters.

\1f
File: quagga.info,  Node: Router Information,  Next: Debugging OSPF,  Prev: OSPF Traffic Engineering,  Up: OSPFv2

7.10 Router Information
=======================

 -- OSPF Command: router-info [as | area <A.B.C.D>]
 -- OSPF Command: no router-info
     Enable Router Information (RFC4970) LSA advertisement with AS scope
     (default) or Area scope flooding when area is specified.

 -- OSPF Command: pce address <A.B.C.D>
 -- OSPF Command: no pce address
 -- OSPF Command: pce domain as <0-65535>
 -- OSPF Command: no pce domain as <0-65535>
 -- OSPF Command: pce neighbor as <0-65535>
 -- OSPF Command: no pce neighbor as <0-65535>
 -- OSPF Command: pce flag BITPATTERN
 -- OSPF Command: no pce flag
 -- OSPF Command: pce scope BITPATTERN
 -- OSPF Command: no pce scope
     The commands are conform to RFC 5088 and allow OSPF router announce
     Path Compuatation Elemenent (PCE) capabilities through the Router
     Information (RI) LSA. Router Information must be enable prior to
     this.  The command set/unset respectively the PCE IP adress,
     Autonomous System (AS) numbers of controlled domains, neighbor ASs,
     flag and scope.  For flag and scope, please refer to RFC5088 for
     the BITPATTERN recognition.  Multiple 'pce neighbor' command could
     be specified in order to specify all PCE neighbours.

 -- Command: show ip ospf router-info
     Show Router Capabilities flag.
 -- Command: show ip ospf router-info pce
     Show Router Capabilities PCE parameters.

\1f
File: quagga.info,  Node: Debugging OSPF,  Next: OSPF Configuration Examples,  Prev: Router Information,  Up: OSPFv2

7.11 Debugging OSPF
===================

 -- Command: debug ospf packet
          (hello|dd|ls-request|ls-update|ls-ack|all) (send|recv)
          [detail]
 -- Command: no debug ospf packet
          (hello|dd|ls-request|ls-update|ls-ack|all) (send|recv)
          [detail]
     Dump Packet for debugging

 -- Command: debug ospf ism
 -- Command: debug ospf ism (status|events|timers)
 -- Command: no debug ospf ism
 -- Command: no debug ospf ism (status|events|timers)
     Show debug information of Interface State Machine

 -- Command: debug ospf nsm
 -- Command: debug ospf nsm (status|events|timers)
 -- Command: no debug ospf nsm
 -- Command: no debug ospf nsm (status|events|timers)
     Show debug information of Network State Machine

 -- Command: debug ospf event
 -- Command: no debug ospf event
     Show debug information of OSPF event

 -- Command: debug ospf nssa
 -- Command: no debug ospf nssa
     Show debug information about Not So Stub Area

 -- Command: debug ospf lsa
 -- Command: debug ospf lsa (generate|flooding|refresh)
 -- Command: no debug ospf lsa
 -- Command: no debug ospf lsa (generate|flooding|refresh)
     Show debug detail of Link State messages

 -- Command: debug ospf te
 -- Command: no debug ospf te
     Show debug information about Traffic Engineering LSA

 -- Command: debug ospf zebra
 -- Command: debug ospf zebra (interface|redistribute)
 -- Command: no debug ospf zebra
 -- Command: no debug ospf zebra (interface|redistribute)
     Show debug information of ZEBRA API

 -- Command: show debugging ospf

\1f
File: quagga.info,  Node: OSPF Configuration Examples,  Prev: Debugging OSPF,  Up: OSPFv2

7.12 OSPF Configuration Examples
================================

A simple example, with MD5 authentication enabled:

     !
     interface bge0
      ip ospf authentication message-digest
      ip ospf message-digest-key 1 md5 ABCDEFGHIJK
     !
     router ospf
      network 192.168.0.0/16 area 0.0.0.1
      area 0.0.0.1 authentication message-digest

   An ABR router, with MD5 authentication and performing summarisation
of networks between the areas:

     !
     password ABCDEF
     log file /var/log/quagga/ospfd.log
     service advanced-vty
     !
     interface eth0
      ip ospf authentication message-digest
      ip ospf message-digest-key 1 md5 ABCDEFGHIJK
     !
     interface ppp0
     !
     interface br0
      ip ospf authentication message-digest
      ip ospf message-digest-key 2 md5 XYZ12345
     !
     router ospf
      ospf router-id 192.168.0.1
      redistribute connected
      passive interface ppp0
      network 192.168.0.0/24 area 0.0.0.0
      network 10.0.0.0/16 area 0.0.0.0
      network 192.168.1.0/24 area 0.0.0.1
      area 0.0.0.0 authentication message-digest
      area 0.0.0.0 range 10.0.0.0/16
      area 0.0.0.0 range 192.168.0.0/24
      area 0.0.0.1 authentication message-digest
      area 0.0.0.1 range 10.2.0.0/16
     !

   A Traffic Engineering configuration, with Inter-ASv2 support.

   - First, the 'zebra.conf' part:

     hostname HOSTNAME
     password PASSWORD
     log file /var/log/zebra.log
     !
     interface eth0
      ip address 198.168.1.1/24
      mpls-te on
      mpls-te link metric 10
      mpls-te link max-bw 1.25e+06
      mpls-te link max-rsv-bw 1.25e+06
      mpls-te link unrsv-bw 0 1.25e+06
      mpls-te link unrsv-bw 1 1.25e+06
      mpls-te link unrsv-bw 2 1.25e+06
      mpls-te link unrsv-bw 3 1.25e+06
      mpls-te link unrsv-bw 4 1.25e+06
      mpls-te link unrsv-bw 5 1.25e+06
      mpls-te link unrsv-bw 6 1.25e+06
      mpls-te link unrsv-bw 7 1.25e+06
      mpls-te link rsc-clsclr 0xab
     !
     interface eth1
      ip address 192.168.2.1/24
      mpls-te on
      mpls-te link metric 10
      mpls-te link max-bw 1.25e+06
      mpls-te link max-rsv-bw 1.25e+06
      mpls-te link unrsv-bw 0 1.25e+06
      mpls-te link unrsv-bw 1 1.25e+06
      mpls-te link unrsv-bw 2 1.25e+06
      mpls-te link unrsv-bw 3 1.25e+06
      mpls-te link unrsv-bw 4 1.25e+06
      mpls-te link unrsv-bw 5 1.25e+06
      mpls-te link unrsv-bw 6 1.25e+06
      mpls-te link unrsv-bw 7 1.25e+06
      mpls-te link rsc-clsclr 0xab
      mpls-te neighbor 192.168.2.2 as 65000

   - Then the 'ospfd.conf' itself:

     hostname HOSTNAME
     password PASSWORD
     log file /var/log/ospfd.log
     !
     !
     interface eth0
      ip ospf hello-interval 60
      ip ospf dead-interval 240
     !
     interface eth1
      ip ospf hello-interval 60
      ip ospf dead-interval 240
     !
     !
     router ospf
      ospf router-id 192.168.1.1
      network 192.168.0.0/16 area 1
      ospf opaque-lsa
       mpls-te
       mpls-te router-address 192.168.1.1
       mpls-te inter-as area 1
     !
     line vty

   A router information example with PCE advsertisement:

     !
     router ospf
      ospf router-id 192.168.1.1
      network 192.168.0.0/16 area 1
      capability opaque
       mpls-te
       mpls-te router-address 192.168.1.1
      router-info area 0.0.0.1
       pce address 192.168.1.1
       pce flag 0x80
       pce domain as 65400
       pce neighbor as 65500
       pce neighbor as 65200
       pce scope 0x80
     !

\1f
File: quagga.info,  Node: OSPFv3,  Next: ISIS,  Prev: OSPFv2,  Up: Top

8 OSPFv3
********

'ospf6d' is a daemon support OSPF version 3 for IPv6 network.  OSPF for
IPv6 is described in RFC2740.

* Menu:

* OSPF6 router::                
* OSPF6 area::                  
* OSPF6 interface::             
* Redistribute routes to OSPF6::  
* Showing OSPF6 information::   
* OSPF6 Configuration Examples::

\1f
File: quagga.info,  Node: OSPF6 router,  Next: OSPF6 area,  Up: OSPFv3

8.1 OSPF6 router
================

 -- Command: router ospf6

 -- OSPF6 Command: router-id A.B.C.D
     Set router's Router-ID.

 -- OSPF6 Command: interface IFNAME area AREA
     Bind interface to specified area, and start sending OSPF packets.
     AREA can be specified as 0.

 -- OSPF6 Command: timers throttle spf DELAY INITIAL-HOLDTIME
          MAX-HOLDTIME
 -- OSPF6 Command: no timers throttle spf
     This command sets the initial DELAY, the INITIAL-HOLDTIME and the
     MAXIMUM-HOLDTIME between when SPF is calculated and the event which
     triggered the calculation.  The times are specified in milliseconds
     and must be in the range of 0 to 600000 milliseconds.

     The DELAY specifies the minimum amount of time to delay SPF
     calculation (hence it affects how long SPF calculation is delayed
     after an event which occurs outside of the holdtime of any previous
     SPF calculation, and also serves as a minimum holdtime).

     Consecutive SPF calculations will always be seperated by at least
     'hold-time' milliseconds.  The hold-time is adaptive and initially
     is set to the INITIAL-HOLDTIME configured with the above command.
     Events which occur within the holdtime of the previous SPF
     calculation will cause the holdtime to be increased by
     INITIAL-HOLDTIME, bounded by the MAXIMUM-HOLDTIME configured with
     this command.  If the adaptive hold-time elapses without any
     SPF-triggering event occuring then the current holdtime is reset to
     the INITIAL-HOLDTIME.

          router ospf6
           timers throttle spf 200 400 10000

     In this example, the DELAY is set to 200ms, the INITIAL HOLDTIME is
     set to 400ms and the MAXIMUM HOLDTIME to 10s.  Hence there will
     always be at least 200ms between an event which requires SPF
     calculation and the actual SPF calculation.  Further consecutive
     SPF calculations will always be seperated by between 400ms to 10s,
     the hold-time increasing by 400ms each time an SPF-triggering event
     occurs within the hold-time of the previous SPF calculation.

 -- OSPF6 Command: auto-cost reference-bandwidth COST
 -- OSPF6 Command: no auto-cost reference-bandwidth
     This sets the reference bandwidth for cost calculations, where this
     bandwidth is considered equivalent to an OSPF cost of 1, specified
     in Mbits/s.  The default is 100Mbit/s (i.e.  a link of bandwidth
     100Mbit/s or higher will have a cost of 1.  Cost of lower bandwidth
     links will be scaled with reference to this cost).

     This configuration setting MUST be consistent across all routers
     within the OSPF domain.

\1f
File: quagga.info,  Node: OSPF6 area,  Next: OSPF6 interface,  Prev: OSPF6 router,  Up: OSPFv3

8.2 OSPF6 area
==============

Area support for OSPFv3 is not yet implemented.

\1f
File: quagga.info,  Node: OSPF6 interface,  Next: Redistribute routes to OSPF6,  Prev: OSPF6 area,  Up: OSPFv3

8.3 OSPF6 interface
===================

 -- Interface Command: ipv6 ospf6 cost COST
     Sets interface's output cost.  Default value depends on the
     interface bandwidth and on the auto-cost reference bandwidth.

 -- Interface Command: ipv6 ospf6 hello-interval HELLOINTERVAL
     Sets interface's Hello Interval.  Default 40

 -- Interface Command: ipv6 ospf6 dead-interval DEADINTERVAL
     Sets interface's Router Dead Interval.  Default value is 40.

 -- Interface Command: ipv6 ospf6 retransmit-interval RETRANSMITINTERVAL
     Sets interface's Rxmt Interval.  Default value is 5.

 -- Interface Command: ipv6 ospf6 priority PRIORITY
     Sets interface's Router Priority.  Default value is 1.

 -- Interface Command: ipv6 ospf6 transmit-delay TRANSMITDELAY
     Sets interface's Inf-Trans-Delay.  Default value is 1.

 -- Interface Command: ipv6 ospf6 network (broadcast|point-to-point)
     Set explicitly network type for specifed interface.

\1f
File: quagga.info,  Node: Redistribute routes to OSPF6,  Next: Showing OSPF6 information,  Prev: OSPF6 interface,  Up: OSPFv3

8.4 Redistribute routes to OSPF6
================================

 -- OSPF6 Command: redistribute static
 -- OSPF6 Command: redistribute connected
 -- OSPF6 Command: redistribute ripng

\1f
File: quagga.info,  Node: Showing OSPF6 information,  Next: OSPF6 Configuration Examples,  Prev: Redistribute routes to OSPF6,  Up: OSPFv3

8.5 Showing OSPF6 information
=============================

 -- Command: show ipv6 ospf6 [INSTANCE_ID]
     INSTANCE_ID is an optional OSPF instance ID. To see router ID and
     OSPF instance ID, simply type "show ipv6 ospf6 <cr>".

 -- Command: show ipv6 ospf6 database
     This command shows LSA database summary.  You can specify the type
     of LSA.

 -- Command: show ipv6 ospf6 interface
     To see OSPF interface configuration like costs.

 -- Command: show ipv6 ospf6 neighbor
     Shows state and chosen (Backup) DR of neighbor.

 -- Command: show ipv6 ospf6 request-list A.B.C.D
     Shows requestlist of neighbor.

 -- Command: show ipv6 route ospf6
     This command shows internal routing table.

\1f
File: quagga.info,  Node: OSPF6 Configuration Examples,  Prev: Showing OSPF6 information,  Up: OSPFv3

8.6 OSPF6 Configuration Examples
================================

Example of ospf6d configured on one interface and area:

     interface eth0
      ipv6 ospf6 instance-id 0
     !
     router ospf6
      router-id 212.17.55.53
      area 0.0.0.0 range 2001:770:105:2::/64
      interface eth0 area 0.0.0.0
     !

\1f
File: quagga.info,  Node: ISIS,  Next: NHRP,  Prev: OSPFv3,  Up: Top

9 ISIS
******

ISIS (Intermediate System to Intermediate System) is a routing protocol
which is described in 'ISO10589, RFC1195, RFC5308'.  ISIS is an IGP
(Interior Gateway Protocol).  Compared with RIP, ISIS can provide
scalable network support and faster convergence times like OSPF.  ISIS
is widely used in large networks such as ISP (Internet Service Provider)
and carrier backbone networks.

* Menu:

* Configuring isisd::
* ISIS router::
* ISIS Timer::
* ISIS region::
* ISIS interface::
* Showing ISIS information::
* ISIS Traffic Engineering::
* Debugging ISIS::
* ISIS Configuration Examples::

\1f
File: quagga.info,  Node: Configuring isisd,  Next: ISIS router,  Up: ISIS

9.1 Configuring isisd
=====================

There are no 'isisd' specific options.  Common options can be specified
(*note Common Invocation Options::) to 'isisd'.  'isisd' needs to
acquire interface information from 'zebra' in order to function.
Therefore 'zebra' must be running before invoking 'isisd'.  Also, if
'zebra' is restarted then 'isisd' must be too.

   Like other daemons, 'isisd' configuration is done in ISIS specific
configuration file 'isisd.conf'.

\1f
File: quagga.info,  Node: ISIS router,  Next: ISIS Timer,  Prev: Configuring isisd,  Up: ISIS

9.2 ISIS router
===============

To start ISIS process you have to specify the ISIS router.  As of this
writing, 'isisd' does not support multiple ISIS processes.

 -- Command: router isis WORD
 -- Command: no router isis WORD
     Enable or disable the ISIS process by specifying the ISIS domain
     with 'WORD'. 'isisd' does not yet support multiple ISIS processes
     but you must specify the name of ISIS process.  The ISIS process
     name 'WORD' is then used for interface (see command *note ip router
     isis WORD::).

 -- ISIS Command: net XX.XXXX. ... .XXX.XX
 -- ISIS Command: no net XX.XXXX. ... .XXX.XX
     Set/Unset network entity title (NET) provided in ISO format.

 -- ISIS Command: hostname dynamic
 -- ISIS Command: no hostname dynamic
     Enable support for dynamic hostname.

 -- ISIS Command: area-password [clear | md5] <password>
 -- ISIS Command: domain-password [clear | md5] <password>
 -- ISIS Command: no area-password
 -- ISIS Command: no domain-password
     Configure the authentication password for an area, respectively a
     domain, as clear text or md5 one.

 -- ISIS Command: log-adjacency-changes
 -- ISIS Command: no log-adjacency-changes
     Log changes in adjacency state.

 -- ISIS Command: metric-style [narrow | transition | wide]
 -- ISIS Command: no metric-style
     Set old-style (ISO 10589) or new-style packet formats: - narrow Use
     old style of TLVs with narrow metric - transition Send and accept
     both styles of TLVs during transition - wide Use new style of TLVs
     to carry wider metric

 -- ISIS Command: set-overload-bit
 -- ISIS Command: no set-overload-bit
     Set overload bit to avoid any transit traffic.

\1f
File: quagga.info,  Node: ISIS Timer,  Next: ISIS region,  Prev: ISIS router,  Up: ISIS

9.3 ISIS Timer
==============

 -- ISIS Command: lsp-gen-interval <1-120>
 -- ISIS Command: lsp-gen-interval [level-1 | level-2] <1-120>
 -- ISIS Command: no lsp-gen-interval
 -- ISIS Command: no lsp-gen-interval [level-1 | level-2]
     Set minimum interval in seconds between regenerating same LSP,
     globally, for an area (level-1) or a domain (level-2).

 -- ISIS Command: lsp-refresh-interval <1-65235>
 -- ISIS Command: lsp-refresh-interval [level-1 | level-2] <1-65235>
 -- ISIS Command: no lsp-refresh-interval
 -- ISIS Command: no lsp-refresh-interval [level-1 | level-2]
     Set LSP refresh interval in seconds, globally, for an area
     (level-1) or a domain (level-2).

 -- ISIS Command: lsp-refresh-interval <1-65235>
 -- ISIS Command: lsp-refresh-interval [level-1 | level-2] <1-65235>
 -- ISIS Command: no lsp-refresh-interval
 -- ISIS Command: no lsp-refresh-interval [level-1 | level-2]
     Set LSP refresh interval in seconds, globally, for an area
     (level-1) or a domain (level-2).

 -- ISIS Command: max-lsp-lifetime <360-65535>
 -- ISIS Command: max-lsp-lifetime [level-1 | level-2] <360-65535>
 -- ISIS Command: no max-lsp-lifetime
 -- ISIS Command: no max-lsp-lifetime [level-1 | level-2]
     Set LSP maximum LSP lifetime in seconds, globally, for an area
     (level-1) or a domain (level-2).

 -- ISIS Command: spf-interval <1-120>
 -- ISIS Command: spf-interval [level-1 | level-2] <1-120>
 -- ISIS Command: no spf-interval
 -- ISIS Command: no spf-interval [level-1 | level-2]
     Set minimum interval between consecutive SPF calculations in
     seconds.

\1f
File: quagga.info,  Node: ISIS region,  Next: ISIS interface,  Prev: ISIS Timer,  Up: ISIS

9.4 ISIS region
===============

 -- ISIS Command: is-type [level-1 | level-1-2 | level-2-only]
 -- ISIS Command: no is-type
     Define the ISIS router behavior: - level-1 Act as a station router
     only - level-1-2 Act as both a station router and an area router -
     level-2-only Act as an area router only

\1f
File: quagga.info,  Node: ISIS interface,  Next: Showing ISIS information,  Prev: ISIS region,  Up: ISIS

9.5 ISIS interface
==================

 -- Interface Command: ip router isis WORD
 -- Interface Command: no ip router isis WORD
     Activate ISIS adjacency on this interface.  Note that the name of
     ISIS instance must be the same as the one used to configure the
     ISIS process (see command *note router isis WORD::).

 -- Interface Command: isis circuit-type [level-1 | level-1-2 | level-2]
 -- Interface Command: no isis circuit-type
     Configure circuit type for interface: - level-1 Level-1 only
     adjacencies are formed - level-1-2 Level-1-2 adjacencies are formed
     - level-2-only Level-2 only adjacencies are formed

 -- Interface Command: isis csnp-interval <1-600>
 -- Interface Command: isis csnp-interval <1-600> [level-1 | level-2]
 -- Interface Command: no isis csnp-interval
 -- Interface Command: no isis csnp-interval [level-1 | level-2]
     Set CSNP interval in seconds globally, for an area (level-1) or a
     domain (level-2).

 -- Interface Command: isis hello padding
     Add padding to IS-IS hello packets.

 -- Interface Command: isis hello-interval <1-600>
 -- Interface Command: isis hello-interval <1-600> [level-1 | level-2]
 -- Interface Command: no isis hello-interval
 -- Interface Command: no isis hello-interval [level-1 | level-2]
     Set Hello interval in seconds globally, for an area (level-1) or a
     domain (level-2).

 -- Interface Command: isis hello-multiplier <2-100>
 -- Interface Command: isis hello-multiplier <2-100> [level-1 | level-2]
 -- Interface Command: no isis hello-multiplier
 -- Interface Command: no isis hello-multiplier [level-1 | level-2]
     Set multiplier for Hello holding time globally, for an area
     (level-1) or a domain (level-2).

 -- Interface Command: isis metric [<0-255> | <0-16777215>]
 -- Interface Command: isis metric [<0-255> | <0-16777215>] [level-1 |
          level-2]
 -- Interface Command: no isis metric
 -- Interface Command: no isis metric [level-1 | level-2]
     Set default metric value globally, for an area (level-1) or a
     domain (level-2).  Max value depend if metric support narrow or
     wide value (see command *note metric-style::).

 -- Interface Command: isis network point-to-point
 -- Interface Command: no isis network point-to-point
     Set network type to 'Point-to-Point' (broadcast by default).

 -- Interface Command: isis passive
 -- Interface Command: no isis passive
     Configure the passive mode for this interface.

 -- Interface Command: isis password [clear | md5] <password>
 -- Interface Command: no isis password
     Configure the authentication password (clear or encoded text) for
     the interface.

 -- Interface Command: isis priority <0-127>
 -- Interface Command: isis priority <0-127> [level-1 | level-2]
 -- Interface Command: no isis priority
 -- Interface Command: no isis priority [level-1 | level-2]
     Set priority for Designated Router election, globally, for the area
     (level-1) or the domain (level-2).

 -- Interface Command: isis psnp-interval <1-120>
 -- Interface Command: isis psnp-interval <1-120> [level-1 | level-2]
 -- Interface Command: no isis psnp-interval
 -- Interface Command: no isis psnp-interval [level-1 | level-2]
     Set PSNP interval in seconds globally, for an area (level-1) or a
     domain (level-2).

\1f
File: quagga.info,  Node: Showing ISIS information,  Next: ISIS Traffic Engineering,  Prev: ISIS interface,  Up: ISIS

9.6 Showing ISIS information
============================

 -- Command: show isis summary
     Show summary information about ISIS.

 -- Command: show isis hostname
     Show information about ISIS node.

 -- Command: show isis interface
 -- Command: show isis interface detail
 -- Command: show isis interface <interface name>
     Show state and configuration of ISIS specified interface, or all
     interfaces if no interface is given with or without details.

 -- Command: show isis neighbor
 -- Command: show isis neighbor <System Id>
 -- Command: show isis neighbor detail
     Show state and information of ISIS specified neighbor, or all
     neighbors if no system id is given with or without details.

 -- Command: show isis database
 -- Command: show isis database [detail]
 -- Command: show isis database <LSP id> [detail]
 -- Command: show isis database detail <LSP id>
     Show the ISIS database globally, for a specific LSP id without or
     with details.

 -- Command: show isis topology
 -- Command: show isis topology [level-1|level-2]
     Show topology IS-IS paths to Intermediate Systems, globally, in
     area (level-1) or domain (level-2).

 -- Command: show ip route isis
     Show the ISIS routing table, as determined by the most recent SPF
     calculation.

\1f
File: quagga.info,  Node: ISIS Traffic Engineering,  Next: Debugging ISIS,  Prev: Showing ISIS information,  Up: ISIS

9.7 Traffic Engineering
=======================

 -- ISIS Command: mpls-te on
 -- ISIS Command: no mpls-te
     Enable Traffic Engineering LSP flooding.

 -- ISIS Command: mpls-te router-address <A.B.C.D>
 -- ISIS Command: no mpls-te router-address
     Configure stable IP address for MPLS-TE.

 -- Command: show isis mpls-te interface
 -- Command: show isis mpls-te interface INTERFACE
     Show MPLS Traffic Engineering parameters for all or specified
     interface.

 -- Command: show isis mpls-te router
     Show Traffic Engineering router parameters.

\1f
File: quagga.info,  Node: Debugging ISIS,  Next: ISIS Configuration Examples,  Prev: ISIS Traffic Engineering,  Up: ISIS

9.8 Debugging ISIS
==================

 -- Command: debug isis adj-packets
 -- Command: no debug isis adj-packets
     IS-IS Adjacency related packets.

 -- Command: debug isis checksum-errors
 -- Command: no debug isis checksum-errors
     IS-IS LSP checksum errors.

 -- Command: debug isis events
 -- Command: no debug isis events
     IS-IS Events.

 -- Command: debug isis local-updates
 -- Command: no debug isis local-updates
     IS-IS local update packets.

 -- Command: debug isis packet-dump
 -- Command: no debug isis packet-dump
     IS-IS packet dump.

 -- Command: debug isis protocol-errors
 -- Command: no debug isis protocol-errors
     IS-IS LSP protocol errors.

 -- Command: debug isis route-events
 -- Command: no debug isis route-events
     IS-IS Route related events.

 -- Command: debug isis snp-packets
 -- Command: no debug isis snp-packets
     IS-IS CSNP/PSNP packets.

 -- Command: debug isis spf-events
 -- Command: debug isis spf-statistics
 -- Command: debug isis spf-triggers
 -- Command: no debug isis spf-events
 -- Command: no debug isis spf-statistics
 -- Command: no debug isis spf-triggers
     IS-IS Shortest Path First Events, Timing and Statistic Data and
     triggering events.

 -- Command: debug isis update-packets
 -- Command: no debug isis update-packets
     Update related packets.

 -- Command: show debugging isis
     Print which ISIS debug level is activate.

\1f
File: quagga.info,  Node: ISIS Configuration Examples,  Prev: Debugging ISIS,  Up: ISIS

9.9 ISIS Configuration Examples
===============================

A simple example, with MD5 authentication enabled:

     !
     interface eth0
      ip router isis FOO
      isis network point-to-point
      isis circuit-type level-2-only
     !
     router isis FOO
     net 47.0023.0000.0000.0000.0000.0000.0000.1900.0004.00
      metric-style wide
      is-type level-2-only

   A Traffic Engineering configuration, with Inter-ASv2 support.

   - First, the 'zebra.conf' part:

     hostname HOSTNAME
     password PASSWORD
     log file /var/log/zebra.log
     !
     interface eth0
      ip address 10.2.2.2/24
      mpls-te on
      mpls-te link metric 10
      mpls-te link max-bw 1.25e+06
      mpls-te link max-rsv-bw 1.25e+06
      mpls-te link unrsv-bw 0 1.25e+06
      mpls-te link unrsv-bw 1 1.25e+06
      mpls-te link unrsv-bw 2 1.25e+06
      mpls-te link unrsv-bw 3 1.25e+06
      mpls-te link unrsv-bw 4 1.25e+06
      mpls-te link unrsv-bw 5 1.25e+06
      mpls-te link unrsv-bw 6 1.25e+06
      mpls-te link unrsv-bw 7 1.25e+06
      mpls-te link rsc-clsclr 0xab
     !
     interface eth1
      ip address 10.1.1.1/24
      mpls-te on
      mpls-te link metric 10
      mpls-te link max-bw 1.25e+06
      mpls-te link max-rsv-bw 1.25e+06
      mpls-te link unrsv-bw 0 1.25e+06
      mpls-te link unrsv-bw 1 1.25e+06
      mpls-te link unrsv-bw 2 1.25e+06
      mpls-te link unrsv-bw 3 1.25e+06
      mpls-te link unrsv-bw 4 1.25e+06
      mpls-te link unrsv-bw 5 1.25e+06
      mpls-te link unrsv-bw 6 1.25e+06
      mpls-te link unrsv-bw 7 1.25e+06
      mpls-te link rsc-clsclr 0xab
      mpls-te neighbor 10.1.1.2 as 65000

   - Then the 'isisd.conf' itself:

     hostname HOSTNAME
     password PASSWORD
     log file /var/log/isisd.log
     !
     !
     interface eth0
      ip router isis FOO
     !
     interface eth1
      ip router isis FOO
     !
     !
     router isis FOO
      isis net 47.0023.0000.0000.0000.0000.0000.0000.1900.0004.00
       mpls-te on
       mpls-te router-address 10.1.1.1
     !
     line vty

\1f
File: quagga.info,  Node: NHRP,  Next: BGP,  Prev: ISIS,  Up: Top

10 NHRP
*******

'nhrpd' is a daemon to support Next Hop Routing Protocol (NHRP). NHRP is
described in RFC2332.

   NHRP is used to improve the efficiency of routing computer network
traffic over Non-Broadcast, Multiple Access (NBMA) Networks.  NHRP
provides an ARP-like solution that allows a system to dynamically learn
the NBMA address of the other systems that are part of that network,
allowing these systems to directly communicate without requiring traffic
to use an intermediate hop.

   Cisco Dynamic Multipoint VPN (DMVPN) is based on NHRP, and Quagga
nrhpd implements this scenario.

* Menu:

* Routing Design::
* Configuring NHRP::
* Hub Functionality::
* Integration with IKE::
* NHRP Events::
* Configuration Example::

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File: quagga.info,  Node: Routing Design,  Next: Configuring NHRP,  Up: NHRP

10.1 Routing Design
===================

nhrpd never handles routing of prefixes itself.  You need to run some
real routing protocol (e.g.  BGP) to advertise routes over the tunnels.
What nhrpd does it establishes 'shortcut routes' that optimizes the
routing protocol to avoid going through extra nodes in NBMA GRE mesh.

   nhrpd does route NHRP domain addresses individually using per-host
prefixes.  This is similar to Cisco FlexVPN; but in contrast to opennhrp
which uses a generic subnet route.

   To create NBMA GRE tunnel you might use the following (linux terminal
commands):
      ip tunnel add gre1 mode gre key 42 ttl 64
      ip addr add 10.255.255.2/32 dev gre1
      ip link set gre1 up

   Note that the IP-address is assigned as host prefix to gre1.  nhrpd
will automatically create additional host routes pointing to gre1 when a
connection with these hosts is established.

   The gre1 subnet prefix should be announced by routing protocol from
the hub nodes (e.g.  BGP 'network' announce).  This allows the routing
protocol to decide which is the closest hub and determine the relay hub
on prefix basis when direct tunnel is not established.

   nhrpd will redistribute directly connected neighbors to zebra.
Within hub nodes, these routes should be internally redistributed using
some routing protocol (e.g.  iBGP) to allow hubs to be able to relay all
traffic.

   This can be achieved in hubs with the following bgp configuration
(network command defines the GRE subnet):
     router bgp 65555
        network 172.16.0.0/16
        redistribute nhrp

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File: quagga.info,  Node: Configuring NHRP,  Next: Hub Functionality,  Prev: Routing Design,  Up: NHRP

10.2 Configuring NHRP
=====================

FIXME

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File: quagga.info,  Node: Hub Functionality,  Next: Integration with IKE,  Prev: Configuring NHRP,  Up: NHRP

10.3 Hub Functionality
======================

In addition to routing nhrp redistributed host prefixes, the hub nodes
are also responsible to send NHRP Traffic Indication messages that
trigger creation of the shortcut tunnels.

   nhrpd sends Traffic Indication messages based on network traffic
captured using NFLOG. Typically you want to send Traffic Indications for
network traffic that is routed from gre1 back to gre1 in rate limited
manner.  This can be achieved with the following iptables rule.

     iptables -A FORWARD -i gre1 -o gre1 \
        -m hashlimit --hashlimit-upto 4/minute --hashlimit-burst 1 \
        --hashlimit-mode srcip,dstip --hashlimit-srcmask 24 \
        --hashlimit-dstmask 24 --hashlimit-name loglimit-0 \
        -j NFLOG --nflog-group 1 --nflog-range 128

   You can fine tune the src/dstmask according to the prefix lengths you
announce internal, add additional IP range matches, or rate limitation
if needed.  However, the above should be good in most cases.

   This kernel NFLOG target's nflog-group is configured in global nhrp
config with:
     nhrp nflog-group 1

   To start sending these traffic notices out from hubs, use the nhrp
per-interface directive:
     interface gre1
      ip nhrp redirect

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File: quagga.info,  Node: Integration with IKE,  Next: NHRP Events,  Prev: Hub Functionality,  Up: NHRP

10.4 Integration with IKE
=========================

nhrpd needs tight integration with IKE daemon for various reasons.
Currently only strongSwan is supported as IKE daemon.

   nhrpd connects to strongSwan using VICI protocol based on UNIX socket
(hardcoded now as /var/run/charon.vici).

   strongSwan currently needs few patches applied.  Please check out the
release
(http://git.alpinelinux.org/cgit/user/tteras/strongswan/log/?h=tteras-release)
and working tree
(http://git.alpinelinux.org/cgit/user/tteras/strongswan/log/?h=tteras)
git repositories for the patches.

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File: quagga.info,  Node: NHRP Events,  Next: Configuration Example,  Prev: Integration with IKE,  Up: NHRP

10.5 NHRP Events
================

FIXME

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File: quagga.info,  Node: Configuration Example,  Prev: NHRP Events,  Up: NHRP

10.6 Configuration Example
==========================

FIXME

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File: quagga.info,  Node: BGP,  Next: Configuring Quagga as a Route Server,  Prev: NHRP,  Up: Top

11 BGP
******

BGP stands for a Border Gateway Protocol.  The lastest BGP version is 4.
It is referred as BGP-4.  BGP-4 is one of the Exterior Gateway Protocols
and de-fact standard of Inter Domain routing protocol.  BGP-4 is
described in 'RFC1771, A Border Gateway Protocol 4 (BGP-4)'.

   Many extensions have been added to 'RFC1771'.  'RFC2858,
Multiprotocol Extensions for BGP-4' provides multiprotocol support to
BGP-4.

* Menu:

* Starting BGP::                
* BGP router::                  
* BGP MED::
* BGP network::                 
* BGP Peer::                    
* BGP Peer Group::              
* BGP Address Family::          
* Autonomous System::           
* BGP Communities Attribute::   
* BGP Extended Communities Attribute::  
* Displaying BGP routes::       
* Capability Negotiation::      
* Route Reflector::             
* Route Server::                
* How to set up a 6-Bone connection::  
* Dump BGP packets and table::  
* BGP Configuration Examples::

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File: quagga.info,  Node: Starting BGP,  Next: BGP router,  Up: BGP

11.1 Starting BGP
=================

Default configuration file of 'bgpd' is 'bgpd.conf'.  'bgpd' searches
the current directory first then /etc/quagga/bgpd.conf.  All of bgpd's
command must be configured in 'bgpd.conf'.

   'bgpd' specific invocation options are described below.  Common
options may also be specified (*note Common Invocation Options::).

'-p PORT'
'--bgp_port=PORT'
     Set the bgp protocol's port number.

'-r'
'--retain'
     When program terminates, retain BGP routes added by zebra.

'-l'
'--listenon'
     Specify a specific IP address for bgpd to listen on, rather than
     its default of INADDR_ANY / IN6ADDR_ANY. This can be useful to
     constrain bgpd to an internal address, or to run multiple bgpd
     processes on one host.

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File: quagga.info,  Node: BGP router,  Next: BGP MED,  Prev: Starting BGP,  Up: BGP

11.2 BGP router
===============

First of all you must configure BGP router with 'router bgp' command.
To configure BGP router, you need AS number.  AS number is an
identification of autonomous system.  BGP protocol uses the AS number
for detecting whether the BGP connection is internal one or external
one.

 -- Command: router bgp ASN
     Enable a BGP protocol process with the specified ASN.  After this
     statement you can input any 'BGP Commands'.  You can not create
     different BGP process under different ASN without specifying
     'multiple-instance' (*note Multiple instance::).

 -- Command: no router bgp ASN
     Destroy a BGP protocol process with the specified ASN.

 -- BGP: bgp router-id A.B.C.D
     This command specifies the router-ID. If 'bgpd' connects to 'zebra'
     it gets interface and address information.  In that case default
     router ID value is selected as the largest IP Address of the
     interfaces.  When 'router zebra' is not enabled 'bgpd' can't get
     interface information so 'router-id' is set to 0.0.0.0.  So please
     set router-id by hand.

* Menu:

* BGP distance::                
* BGP decision process::        
* BGP route flap dampening::      

\1f
File: quagga.info,  Node: BGP distance,  Next: BGP decision process,  Up: BGP router

11.2.1 BGP distance
-------------------

 -- BGP: distance bgp <1-255> <1-255> <1-255>
     This command change distance value of BGP. Each argument is
     distance value for external routes, internal routes and local
     routes.

     To have this command applied to existing routes requires a hard
     clear.

 -- BGP: distance <1-255> A.B.C.D/M
 -- BGP: distance <1-255> A.B.C.D/M WORD
     This command set distance value to

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File: quagga.info,  Node: BGP decision process,  Next: BGP route flap dampening,  Prev: BGP distance,  Up: BGP router

11.2.2 BGP decision process
---------------------------

The decision process Quagga BGP uses to select routes is as follows:

1. Weight check
     prefer higher local weight routes to lower routes.

2. Local preference check
     prefer higher local preference routes to lower.

3. Local route check
     Prefer local routes (statics, aggregates, redistributed) to
     received routes.

4. AS path length check
     Prefer shortest hop-count AS_PATHs.

5. Origin check
     Prefer the lowest origin type route.  That is, prefer IGP origin
     routes to EGP, to Incomplete routes.

6. MED check
     Where routes with a MED were received from the same AS, prefer the
     route with the lowest MED. *Note BGP MED::.

7. External check
     Prefer the route received from an external, eBGP peer over routes
     received from other types of peers.

8. IGP cost check
     Prefer the route with the lower IGP cost.

9. Multi-path check
     If multi-pathing is enabled, then check whether the routes not yet
     distinguished in preference may be considered equal.  If *note bgp
     bestpath as-path multipath-relax:: is set, all such routes are
     considered equal, otherwise routes received via iBGP with identical
     AS_PATHs or routes received from eBGP neighbours in the same AS are
     considered equal.

10 Already-selected external check

     Where both routes were received from eBGP peers, then prefer the
     route which is already selected.  Note that this check is not
     applied if *note bgp bestpath compare-routerid:: is configured.
     This check can prevent some cases of oscillation.

11. Router-ID check
     Prefer the route with the lowest router-ID. If the route has an
     ORIGINATOR_ID attribute, through iBGP reflection, then that router
     ID is used, otherwise the router-ID of the peer the route was
     received from is used.

12. Cluster-List length check
     The route with the shortest cluster-list length is used.  The
     cluster-list reflects the iBGP reflection path the route has taken.

13. Peer address
     Prefer the route received from the peer with the higher transport
     layer address, as a last-resort tie-breaker.

 -- BGP: bgp bestpath as-path confed
     This command specifies that the length of confederation path sets
     and sequences should should be taken into account during the BGP
     best path decision process.

 -- BGP: bgp bestpath as-path multipath-relax
     This command specifies that BGP decision process should consider
     paths of equal AS_PATH length candidates for multipath computation.
     Without the knob, the entire AS_PATH must match for multipath
     computation.

 -- BGP: bgp bestpath compare-routerid

     Ensure that when comparing routes where both are equal on most
     metrics, including local-pref, AS_PATH length, IGP cost, MED, that
     the tie is broken based on router-ID.

     If this option is enabled, then the already-selected check, where
     already selected eBGP routes are preferred, is skipped.

     If a route has an ORIGINATOR_ID attribute because it has been
     reflected, that ORIGINATOR_ID will be used.  Otherwise, the
     router-ID of the peer the route was received from will be used.

     The advantage of this is that the route-selection (at this point)
     will be more deterministic.  The disadvantage is that a few or even
     one lowest-ID router may attract all trafic to otherwise-equal
     paths because of this check.  It may increase the possibility of
     MED or IGP oscillation, unless other measures were taken to avoid
     these.  The exact behaviour will be sensitive to the iBGP and
     reflection topology.

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File: quagga.info,  Node: BGP route flap dampening,  Prev: BGP decision process,  Up: BGP router

11.2.3 BGP route flap dampening
-------------------------------

 -- BGP: bgp dampening <1-45> <1-20000> <1-20000> <1-255>
     This command enables BGP route-flap dampening and specifies
     dampening parameters.

     half-life
          Half-life time for the penalty
     reuse-threshold
          Value to start reusing a route
     suppress-threshold
          Value to start suppressing a route
     max-suppress
          Maximum duration to suppress a stable route

     The route-flap damping algorithm is compatible with 'RFC2439'.  The
     use of this command is not recommended nowadays, see RIPE-378.

\1f
File: quagga.info,  Node: BGP MED,  Next: BGP network,  Prev: BGP router,  Up: BGP

11.3 BGP MED
============

The BGP MED (Multi_Exit_Discriminator) attribute has properties which
can cause subtle convergence problems in BGP. These properties and
problems have proven to be hard to understand, at least historically,
and may still not be widely understood.  The following attempts to
collect together and present what is known about MED, to help operators
and Quagga users in designing and configuring their networks.

   The BGP MED (Multi_Exit_Discriminator) attribute is intended to allow
one AS to indicate its preferences for its ingress points to another AS.
The MED attribute will not be propagated on to another AS by the
receiving AS - it is 'non-transitive' in the BGP sense.

   E.g., if AS X and AS Y have 2 different BGP peering points, then AS X
might set a MED of 100 on routes advertised at one and a MED of 200 at
the other.  When AS Y selects between otherwise equal routes to or via
AS X, AS Y should prefer to take the path via the lower MED peering of
100 with AS X. Setting the MED allows an AS to influence the routing
taken to it within another, neighbouring AS.

   In this use of MED it is not really meaningful to compare the MED
value on routes where the next AS on the paths differs.  E.g., if AS Y
also had a route for some destination via AS Z in addition to the routes
from AS X, and AS Z had also set a MED, it wouldn't make sense for AS Y
to compare AS Z's MED values to those of AS X. The MED values have been
set by different administrators, with different frames of reference.

   The default behaviour of BGP therefore is to not compare MED values
across routes received from different neighbouring ASes.  In Quagga this
is done by comparing the neighbouring, left-most AS in the received
AS_PATHs of the routes and only comparing MED if those are the same.

   Unfortunately, this behaviour of MED, of sometimes being compared
across routes and sometimes not, depending on the properties of those
other routes, means MED can cause the order of preference over all the
routes to be undefined.  That is, given routes A, B, and C, if A is
preferred to B, and B is preferred to C, then a well-defined order
should mean the preference is transitive (in the sense of orders (1))
and that A would be preferred to C.

   However, when MED is involved this need not be the case.  With MED it
is possible that C is actually preferred over A. So A is preferred to B,
B is preferred to C, but C is preferred to A. This can be true even
where BGP defines a deterministic "most preferred" route out of the full
set of A,B,C. With MED, for any given set of routes there may be a
deterministically preferred route, but there need not be any way to
arrange them into any order of preference.  With unmodified MED, the
order of preference of routes literally becomes undefined.

   That MED can induce non-transitive preferences over routes can cause
issues.  Firstly, it may be perceived to cause routing table churn
locally at speakers; secondly, and more seriously, it may cause routing
instability in iBGP topologies, where sets of speakers continually
oscillate between different paths.

   The first issue arises from how speakers often implement routing
decisions.  Though BGP defines a selection process that will
deterministically select the same route as best at any given speaker,
even with MED, that process requires evaluating all routes together.
For performance and ease of implementation reasons, many implementations
evaluate route preferences in a pair-wise fashion instead.  Given there
is no well-defined order when MED is involved, the best route that will
be chosen becomes subject to implementation details, such as the order
the routes are stored in.  That may be (locally) non-deterministic, e.g.
it may be the order the routes were received in.

   This indeterminism may be considered undesirable, though it need not
cause problems.  It may mean additional routing churn is perceived, as
sometimes more updates may be produced than at other times in reaction
to some event .

   This first issue can be fixed with a more deterministic route
selection that ensures routes are ordered by the neighbouring AS during
selection.  *Note bgp deterministic-med::.  This may reduce the number
of updates as routes are received, and may in some cases reduce routing
churn.  Though, it could equally deterministically produce the largest
possible set of updates in response to the most common sequence of
received updates.

   A deterministic order of evaluation tends to imply an additional
overhead of sorting over any set of n routes to a destination.  The
implementation of deterministic MED in Quagga scales significantly worse
than most sorting algorithms at present, with the number of paths to a
given destination.  That number is often low enough to not cause any
issues, but where there are many paths, the deterministic comparison may
quickly become increasingly expensive in terms of CPU.

   Deterministic local evaluation can _not_ fix the second, more major,
issue of MED however.  Which is that the non-transitive preference of
routes MED can cause may lead to routing instability or oscillation
across multiple speakers in iBGP topologies.  This can occur with
full-mesh iBGP, but is particularly problematic in non-full-mesh iBGP
topologies that further reduce the routing information known to each
speaker.  This has primarily been documented with iBGP route-reflection
topologies.  However, any route-hiding technologies potentially could
also exacerbate oscillation with MED.

   This second issue occurs where speakers each have only a subset of
routes, and there are cycles in the preferences between different
combinations of routes - as the undefined order of preference of MED
allows - and the routes are distributed in a way that causes the BGP
speakers to 'chase' those cycles.  This can occur even if all speakers
use a deterministic order of evaluation in route selection.

   E.g., speaker 4 in AS A might receive a route from speaker 2 in AS X,
and from speaker 3 in AS Y; while speaker 5 in AS A might receive that
route from speaker 1 in AS Y. AS Y might set a MED of 200 at speaker 1,
and 100 at speaker 3.  I.e, using ASN:ID:MED to label the speakers:


                /---------------\
      X:2------|--A:4-------A:5--|-Y:1:200
      Y:3:100--|-/               |
                \---------------/


   Assuming all other metrics are equal (AS_PATH, ORIGIN, 0 IGP costs),
then based on the RFC4271 decision process speaker 4 will choose X:2
over Y:3:100, based on the lower ID of 2.  Speaker 4 advertises X:2 to
speaker 5.  Speaker 5 will continue to prefer Y:1:200 based on the ID,
and advertise this to speaker 4.  Speaker 4 will now have the full set
of routes, and the Y:1:200 it receives from 5 will beat X:2, but when
speaker 4 compares Y:1:200 to Y:3:100 the MED check now becomes active
as the ASes match, and now Y:3:100 is preferred.  Speaker 4 therefore
now advertises Y:3:100 to 5, which will also agrees that Y:3:100 is
preferred to Y:1:200, and so withdraws the latter route from 4.  Speaker
4 now has only X:2 and Y:3:100, and X:2 beats Y:3:100, and so speaker 4
implicitly updates its route to speaker 5 to X:2.  Speaker 5 sees that
Y:1:200 beats X:2 based on the ID, and advertises Y:1:200 to speaker 4,
and the cycle continues.

   The root cause is the lack of a clear order of preference caused by
how MED sometimes is and sometimes is not compared, leading to this
cycle in the preferences between the routes:


            /---> X:2 ---beats---> Y:3:100 --\
           |                                  |
           |                                  |
            \---beats--- Y:1:200 <---beats---/


   This particular type of oscillation in full-mesh iBGP topologies can
be avoided by speakers preferring already selected, external routes
rather than choosing to update to new a route based on a post-MED metric
(e.g.  router-ID), at the cost of a non-deterministic selection process.
Quagga implements this, as do many other implementations, so long as it
is not overridden by setting *note bgp bestpath compare-routerid::, and
see also *note BGP decision process::, .

   However, more complex and insidious cycles of oscillation are
possible with iBGP route-reflection, which are not so easily avoided.
These have been documented in various places.  See, e.g., 'McPherson, D.
and Gill, V. and Walton, D., "Border Gateway Protocol (BGP) Persistent
Route Oscillation Condition", IETF RFC3345', and 'Flavel, A. and M.
Roughan, "Stable and flexible iBGP", ACM SIGCOMM 2009', and 'Griffin, T.
and G. Wilfong, "On the correctness of IBGP configuration", ACM SIGCOMM
2002' for concrete examples and further references.

   There is as of this writing _no_ known way to use MED for its
original purpose; _and_ reduce routing information in iBGP topologies;
_and_ be sure to avoid the instability problems of MED due the
non-transitive routing preferences it can induce; in general on
arbitrary networks.

   There may be iBGP topology specific ways to reduce the instability
risks, even while using MED, e.g. by constraining the reflection
topology and by tuning IGP costs between route-reflector clusters, see
RFC3345 for details.  In the near future, the Add-Path extension to BGP
may also solve MED oscillation while still allowing MED to be used as
intended, by distributing "best-paths per neighbour AS". This would be
at the cost of distributing at least as many routes to all speakers as a
full-mesh iBGP would, if not more, while also imposing similar CPU
overheads as the "Deterministic MED" feature at each Add-Path reflector.

   More generally, the instability problems that MED can introduce on
more complex, non-full-mesh, iBGP topologies may be avoided either by:

   * Setting *note bgp always-compare-med::, however this allows MED to
     be compared across values set by different neighbour ASes, which
     may not produce coherent desirable results, of itself.

   * Effectively ignoring MED by setting MED to the same value (e.g. 0)
     using *note routemap set metric:: on all received routes, in
     combination with setting *note bgp always-compare-med:: on all
     speakers.  This is the simplest and most performant way to avoid
     MED oscillation issues, where an AS is happy not to allow
     neighbours to inject this problematic metric.

   As MED is evaluated after the AS_PATH length check, another possible
use for MED is for intra-AS steering of routes with equal AS_PATH
length, as an extension of the last case above.  As MED is evaluated
before IGP metric, this can allow cold-potato routing to be implemented
to send traffic to preferred hand-offs with neighbours, rather than the
closest hand-off according to the IGP metric.

   Note that even if action is taken to address the MED non-transitivity
issues, other oscillations may still be possible.  E.g., on IGP cost if
iBGP and IGP topologies are at cross-purposes with each other - see the
Flavel and Roughan paper above for an example.  Hence the guideline that
the iBGP topology should follow the IGP topology.

 -- BGP: bgp deterministic-med

     Carry out route-selection in way that produces deterministic
     answers locally, even in the face of MED and the lack of a
     well-defined order of preference it can induce on routes.  Without
     this option the preferred route with MED may be determined largely
     by the order that routes were received in.

     Setting this option will have a performance cost that may be
     noticeable when there are many routes for each destination.
     Currently in Quagga it is implemented in a way that scales poorly
     as the number of routes per destination increases.

     The default is that this option is not set.

   Note that there are other sources of indeterminism in the route
selection process, specifically, the preference for older and already
selected routes from eBGP peers, *Note BGP decision process::.

 -- BGP: bgp always-compare-med

     Always compare the MED on routes, even when they were received from
     different neighbouring ASes.  Setting this option makes the order
     of preference of routes more defined, and should eliminate MED
     induced oscillations.

     If using this option, it may also be desirable to use *note
     routemap set metric:: to set MED to 0 on routes received from
     external neighbours.

     This option can be used, together with *note routemap set metric::
     to use MED as an intra-AS metric to steer equal-length AS_PATH
     routes to, e.g., desired exit points.

   ---------- Footnotes ----------

   (1) For some set of objects to have an order, there _must_ be some
binary ordering relation that is defined for _every_ combination of
those objects, and that relation _must_ be transitive.  I.e., if the
relation operator is ≺, and if a ≺ b and b ≺ c then that relation
must carry over and it _must_ be that a ≺ c for the objects to have an
order.  The ordering relation may allow for equality, i.e.  a ≺ b and
b ≺ a may both be true amd imply that a and b are equal in the order
and not distinguished by it, in which case the set has a partial order.
Otherwise, if there is an order, all the objects have a distinct place
in the order and the set has a total order.

\1f
File: quagga.info,  Node: BGP network,  Next: BGP Peer,  Prev: BGP MED,  Up: BGP

11.4 BGP network
================

* Menu:

* BGP route::                   
* Route Aggregation::           
* Redistribute to BGP::         

\1f
File: quagga.info,  Node: BGP route,  Next: Route Aggregation,  Up: BGP network

11.4.1 BGP route
----------------

 -- BGP: network A.B.C.D/M
     This command adds the announcement network.
          router bgp 1
           network 10.0.0.0/8
     This configuration example says that network 10.0.0.0/8 will be
     announced to all neighbors.  Some vendors' routers don't advertise
     routes if they aren't present in their IGP routing tables; 'bgpd'
     doesn't care about IGP routes when announcing its routes.

 -- BGP: no network A.B.C.D/M

\1f
File: quagga.info,  Node: Route Aggregation,  Next: Redistribute to BGP,  Prev: BGP route,  Up: BGP network

11.4.2 Route Aggregation
------------------------

 -- BGP: aggregate-address A.B.C.D/M
     This command specifies an aggregate address.

 -- BGP: aggregate-address A.B.C.D/M as-set
     This command specifies an aggregate address.  Resulting routes
     include AS set.

 -- BGP: aggregate-address A.B.C.D/M summary-only
     This command specifies an aggregate address.  Aggreated routes will
     not be announce.

 -- BGP: no aggregate-address A.B.C.D/M

\1f
File: quagga.info,  Node: Redistribute to BGP,  Prev: Route Aggregation,  Up: BGP network

11.4.3 Redistribute to BGP
--------------------------

 -- BGP: redistribute kernel
     Redistribute kernel route to BGP process.

 -- BGP: redistribute static
     Redistribute static route to BGP process.

 -- BGP: redistribute connected
     Redistribute connected route to BGP process.

 -- BGP: redistribute rip
     Redistribute RIP route to BGP process.

 -- BGP: redistribute ospf
     Redistribute OSPF route to BGP process.

\1f
File: quagga.info,  Node: BGP Peer,  Next: BGP Peer Group,  Prev: BGP network,  Up: BGP

11.5 BGP Peer
=============

* Menu:

* Defining Peer::               
* BGP Peer commands::           
* Peer filtering::              

\1f
File: quagga.info,  Node: Defining Peer,  Next: BGP Peer commands,  Up: BGP Peer

11.5.1 Defining Peer
--------------------

 -- BGP: neighbor PEER remote-as ASN
     Creates a new neighbor whose remote-as is ASN.  PEER can be an IPv4
     address or an IPv6 address.
          router bgp 1
           neighbor 10.0.0.1 remote-as 2
     In this case my router, in AS-1, is trying to peer with AS-2 at
     10.0.0.1.

     This command must be the first command used when configuring a
     neighbor.  If the remote-as is not specified, 'bgpd' will complain
     like this:
          can't find neighbor 10.0.0.1

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File: quagga.info,  Node: BGP Peer commands,  Next: Peer filtering,  Prev: Defining Peer,  Up: BGP Peer

11.5.2 BGP Peer commands
------------------------

In a 'router bgp' clause there are neighbor specific configurations
required.

 -- BGP: neighbor PEER shutdown
 -- BGP: no neighbor PEER shutdown
     Shutdown the peer.  We can delete the neighbor's configuration by
     'no neighbor PEER remote-as AS-NUMBER' but all configuration of the
     neighbor will be deleted.  When you want to preserve the
     configuration, but want to drop the BGP peer, use this syntax.

 -- BGP: neighbor PEER ebgp-multihop
 -- BGP: no neighbor PEER ebgp-multihop

 -- BGP: neighbor PEER description ...
 -- BGP: no neighbor PEER description ...
     Set description of the peer.

 -- BGP: neighbor PEER version VERSION
     Set up the neighbor's BGP version.  VERSION can be 4, 4+ or 4-.
     BGP version 4 is the default value used for BGP peering.  BGP
     version 4+ means that the neighbor supports Multiprotocol
     Extensions for BGP-4.  BGP version 4- is similar but the neighbor
     speaks the old Internet-Draft revision 00's Multiprotocol
     Extensions for BGP-4.  Some routing software is still using this
     version.

 -- BGP: neighbor PEER interface IFNAME
 -- BGP: no neighbor PEER interface IFNAME
     When you connect to a BGP peer over an IPv6 link-local address, you
     have to specify the IFNAME of the interface used for the
     connection.  To specify IPv4 session addresses, see the 'neighbor
     PEER update-source' command below.

     This command is deprecated and may be removed in a future release.
     Its use should be avoided.

 -- BGP: neighbor PEER next-hop-self [all]
 -- BGP: no neighbor PEER next-hop-self [all]
     This command specifies an announced route's nexthop as being
     equivalent to the address of the bgp router if it is learned via
     eBGP. If the optional keyword 'all' is specified the modifiation is
     done also for routes learned via iBGP.

 -- BGP: neighbor PEER update-source <IFNAME|ADDRESS>
 -- BGP: no neighbor PEER update-source
     Specify the IPv4 source address to use for the BGP session to this
     neighbour, may be specified as either an IPv4 address directly or
     as an interface name (in which case the 'zebra' daemon MUST be
     running in order for 'bgpd' to be able to retrieve interface
     state).
          router bgp 64555
           neighbor foo update-source 192.168.0.1
           neighbor bar update-source lo0

 -- BGP: neighbor PEER default-originate
 -- BGP: no neighbor PEER default-originate
     'bgpd''s default is to not announce the default route (0.0.0.0/0)
     even it is in routing table.  When you want to announce default
     routes to the peer, use this command.

 -- BGP: neighbor PEER port PORT
 -- BGP: neighbor PEER port PORT

 -- BGP: neighbor PEER send-community
 -- BGP: neighbor PEER send-community

 -- BGP: neighbor PEER weight WEIGHT
 -- BGP: no neighbor PEER weight WEIGHT
     This command specifies a default WEIGHT value for the neighbor's
     routes.

 -- BGP: neighbor PEER maximum-prefix NUMBER
 -- BGP: no neighbor PEER maximum-prefix NUMBER

 -- BGP: neighbor PEER local-as AS-NUMBER
 -- BGP: neighbor PEER local-as AS-NUMBER no-prepend
 -- BGP: neighbor PEER local-as AS-NUMBER no-prepend replace-as
 -- BGP: no neighbor PEER local-as
     Specify an alternate AS for this BGP process when interacting with
     the specified peer.  With no modifiers, the specified local-as is
     prepended to the received AS_PATH when receiving routing updates
     from the peer, and prepended to the outgoing AS_PATH (after the
     process local AS) when transmitting local routes to the peer.

     If the no-prepend attribute is specified, then the supplied
     local-as is not prepended to the received AS_PATH.

     If the replace-as attribute is specified, then only the supplied
     local-as is prepended to the AS_PATH when transmitting local-route
     updates to this peer.

     Note that replace-as can only be specified if no-prepend is.

     This command is only allowed for eBGP peers.

 -- BGP: neighbor PEER ttl-security hops NUMBER
 -- BGP: no neighbor PEER ttl-security hops NUMBER
     This command enforces Generalized TTL Security Mechanism (GTSM), as
     specified in RFC 5082.  With this command, only neighbors that are
     the specified number of hops away will be allowed to become
     neighbors.  This command is mututally exclusive with
     'ebgp-multihop'.

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File: quagga.info,  Node: Peer filtering,  Prev: BGP Peer commands,  Up: BGP Peer

11.5.3 Peer filtering
---------------------

 -- BGP: neighbor PEER distribute-list NAME [in|out]
     This command specifies a distribute-list for the peer.  DIRECT is
     'in' or 'out'.

 -- BGP command: neighbor PEER prefix-list NAME [in|out]

 -- BGP command: neighbor PEER filter-list NAME [in|out]

 -- BGP: neighbor PEER route-map NAME [in|out]
     Apply a route-map on the neighbor.  DIRECT must be 'in' or 'out'.

 -- BGP: bgp route-reflector allow-outbound-policy
     By default, attribute modification via route-map policy out is not
     reflected on reflected routes.  This option allows the
     modifications to be reflected as well.  Once enabled, it affects
     all reflected routes.

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File: quagga.info,  Node: BGP Peer Group,  Next: BGP Address Family,  Prev: BGP Peer,  Up: BGP

11.6 BGP Peer Group
===================

 -- BGP: neighbor WORD peer-group
     This command defines a new peer group.

 -- BGP: neighbor PEER peer-group WORD
     This command bind specific peer to peer group WORD.

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File: quagga.info,  Node: BGP Address Family,  Next: Autonomous System,  Prev: BGP Peer Group,  Up: BGP

11.7 BGP Address Family
=======================

Multiprotocol BGP enables BGP to carry routing information for multiple
Network Layer protocols.  BGP supports multiple Address Family
Identifier (AFI), namely IPv4 and IPv6.  Support is also provided for
multiple sets of per-AFI information via Subsequent Address Family
Identifiers (SAFI). In addition to unicast information, VPN information
'RFC4364' and 'RFC4659', and Encapsulation information 'RFC5512' is
supported.

 -- Command: show ip bgp vpnv4 all
 -- Command: show ipv6 bgp vpn all
     Print active IPV4 or IPV6 routes advertised via the VPN SAFI.

 -- Command: show ip bgp encap all
 -- Command: show ipv6 bgp encap all
     Print active IPV4 or IPV6 routes advertised via the Encapsulation
     SAFI.

 -- Command: show bgp ipv4 encap summary
 -- Command: show bgp ipv4 vpn summary
 -- Command: show bgp ipv6 encap summary
 -- Command: show bgp ipv6 vpn summary
     Print a summary of neighbor connections for the specified AFI/SAFI
     combination.

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File: quagga.info,  Node: Autonomous System,  Next: BGP Communities Attribute,  Prev: BGP Address Family,  Up: BGP

11.8 Autonomous System
======================

The AS (Autonomous System) number is one of the essential element of
BGP. BGP is a distance vector routing protocol, and the AS-Path
framework provides distance vector metric and loop detection to BGP.
'RFC1930, Guidelines for creation, selection, and registration of an
Autonomous System (AS)' provides some background on the concepts of an
AS.

   The AS number is a two octet value, ranging in value from 1 to 65535.
The AS numbers 64512 through 65535 are defined as private AS numbers.
Private AS numbers must not to be advertised in the global Internet.

* Menu:

* AS Path Regular Expression::  
* Display BGP Routes by AS Path::  
* AS Path Access List::         
* Using AS Path in Route Map::  
* Private AS Numbers::          

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File: quagga.info,  Node: AS Path Regular Expression,  Next: Display BGP Routes by AS Path,  Up: Autonomous System

11.8.1 AS Path Regular Expression
---------------------------------

AS path regular expression can be used for displaying BGP routes and AS
path access list.  AS path regular expression is based on 'POSIX 1003.2'
regular expressions.  Following description is just a subset of 'POSIX'
regular expression.  User can use full 'POSIX' regular expression.
Adding to that special character '_' is added for AS path regular
expression.

'.'
     Matches any single character.
'*'
     Matches 0 or more occurrences of pattern.
'+'
     Matches 1 or more occurrences of pattern.
'?'
     Match 0 or 1 occurrences of pattern.
'^'
     Matches the beginning of the line.
'$'
     Matches the end of the line.
'_'
     Character '_' has special meanings in AS path regular expression.
     It matches to space and comma , and AS set delimiter { and } and AS
     confederation delimiter '(' and ')'.  And it also matches to the
     beginning of the line and the end of the line.  So '_' can be used
     for AS value boundaries match.  'show ip bgp regexp _7675_' matches
     to all of BGP routes which as AS number include 7675.

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File: quagga.info,  Node: Display BGP Routes by AS Path,  Next: AS Path Access List,  Prev: AS Path Regular Expression,  Up: Autonomous System

11.8.2 Display BGP Routes by AS Path
------------------------------------

To show BGP routes which has specific AS path information 'show ip bgp'
command can be used.

 -- Command: show ip bgp regexp LINE
     This commands display BGP routes that matches AS path regular
     expression LINE.

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File: quagga.info,  Node: AS Path Access List,  Next: Using AS Path in Route Map,  Prev: Display BGP Routes by AS Path,  Up: Autonomous System

11.8.3 AS Path Access List
--------------------------

AS path access list is user defined AS path.

 -- Command: ip as-path access-list WORD {permit|deny} LINE
     This command defines a new AS path access list.

 -- Command: no ip as-path access-list WORD
 -- Command: no ip as-path access-list WORD {permit|deny} LINE

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File: quagga.info,  Node: Using AS Path in Route Map,  Next: Private AS Numbers,  Prev: AS Path Access List,  Up: Autonomous System

11.8.4 Using AS Path in Route Map
---------------------------------

 -- Route Map: match as-path WORD

 -- Route Map: set as-path prepend AS-PATH
     Prepend the given string of AS numbers to the AS_PATH.

 -- Route Map: set as-path prepend last-as NUM
     Prepend the existing last AS number (the leftmost ASN) to the
     AS_PATH.

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File: quagga.info,  Node: Private AS Numbers,  Prev: Using AS Path in Route Map,  Up: Autonomous System

11.8.5 Private AS Numbers
-------------------------

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File: quagga.info,  Node: BGP Communities Attribute,  Next: BGP Extended Communities Attribute,  Prev: Autonomous System,  Up: BGP

11.9 BGP Communities Attribute
==============================

BGP communities attribute is widely used for implementing policy
routing.  Network operators can manipulate BGP communities attribute
based on their network policy.  BGP communities attribute is defined in
'RFC1997, BGP Communities Attribute' and 'RFC1998, An Application of the
BGP Community Attribute in Multi-home Routing'.  It is an optional
transitive attribute, therefore local policy can travel through
different autonomous system.

   Communities attribute is a set of communities values.  Each
communities value is 4 octet long.  The following format is used to
define communities value.

'AS:VAL'
     This format represents 4 octet communities value.  'AS' is high
     order 2 octet in digit format.  'VAL' is low order 2 octet in digit
     format.  This format is useful to define AS oriented policy value.
     For example, '7675:80' can be used when AS 7675 wants to pass local
     policy value 80 to neighboring peer.
'internet'
     'internet' represents well-known communities value 0.
'no-export'
     'no-export' represents well-known communities value 'NO_EXPORT'
     (0xFFFFFF01).  All routes carry this value must not be advertised
     to outside a BGP confederation boundary.  If neighboring BGP peer
     is part of BGP confederation, the peer is considered as inside a
     BGP confederation boundary, so the route will be announced to the
     peer.
'no-advertise'
     'no-advertise' represents well-known communities value
     'NO_ADVERTISE'
     (0xFFFFFF02).  All routes carry this value must not be advertise to
     other BGP peers.
'local-AS'
     'local-AS' represents well-known communities value
     'NO_EXPORT_SUBCONFED' (0xFFFFFF03).  All routes carry this value
     must not be advertised to external BGP peers.  Even if the
     neighboring router is part of confederation, it is considered as
     external BGP peer, so the route will not be announced to the peer.

   When BGP communities attribute is received, duplicated communities
value in the communities attribute is ignored and each communities
values are sorted in numerical order.

* Menu:

* BGP Community Lists::         
* Numbered BGP Community Lists::  
* BGP Community in Route Map::  
* Display BGP Routes by Community::  
* Using BGP Communities Attribute::  

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File: quagga.info,  Node: BGP Community Lists,  Next: Numbered BGP Community Lists,  Up: BGP Communities Attribute

11.9.1 BGP Community Lists
--------------------------

BGP community list is a user defined BGP communites attribute list.  BGP
community list can be used for matching or manipulating BGP communities
attribute in updates.

   There are two types of community list.  One is standard community
list and another is expanded community list.  Standard community list
defines communities attribute.  Expanded community list defines
communities attribute string with regular expression.  Standard
community list is compiled into binary format when user define it.
Standard community list will be directly compared to BGP communities
attribute in BGP updates.  Therefore the comparison is faster than
expanded community list.

 -- Command: ip community-list standard NAME {permit|deny} COMMUNITY
     This command defines a new standard community list.  COMMUNITY is
     communities value.  The COMMUNITY is compiled into community
     structure.  We can define multiple community list under same name.
     In that case match will happen user defined order.  Once the
     community list matches to communities attribute in BGP updates it
     return permit or deny by the community list definition.  When there
     is no matched entry, deny will be returned.  When COMMUNITY is
     empty it matches to any routes.

 -- Command: ip community-list expanded NAME {permit|deny} LINE
     This command defines a new expanded community list.  LINE is a
     string expression of communities attribute.  LINE can include
     regular expression to match communities attribute in BGP updates.

 -- Command: no ip community-list NAME
 -- Command: no ip community-list standard NAME
 -- Command: no ip community-list expanded NAME
     These commands delete community lists specified by NAME.  All of
     community lists shares a single name space.  So community lists can
     be removed simpley specifying community lists name.

 -- Command: show ip community-list
 -- Command: show ip community-list NAME
     This command display current community list information.  When NAME
     is specified the specified community list's information is shown.

          # show ip community-list
          Named Community standard list CLIST
              permit 7675:80 7675:100 no-export
              deny internet
          Named Community expanded list EXPAND
              permit :

          # show ip community-list CLIST
          Named Community standard list CLIST
              permit 7675:80 7675:100 no-export
              deny internet

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File: quagga.info,  Node: Numbered BGP Community Lists,  Next: BGP Community in Route Map,  Prev: BGP Community Lists,  Up: BGP Communities Attribute

11.9.2 Numbered BGP Community Lists
-----------------------------------

When number is used for BGP community list name, the number has special
meanings.  Community list number in the range from 1 and 99 is standard
community list.  Community list number in the range from 100 to 199 is
expanded community list.  These community lists are called as numbered
community lists.  On the other hand normal community lists is called as
named community lists.

 -- Command: ip community-list <1-99> {permit|deny} COMMUNITY
     This command defines a new community list.  <1-99> is standard
     community list number.  Community list name within this range
     defines standard community list.  When COMMUNITY is empty it
     matches to any routes.

 -- Command: ip community-list <100-199> {permit|deny} COMMUNITY
     This command defines a new community list.  <100-199> is expanded
     community list number.  Community list name within this range
     defines expanded community list.

 -- Command: ip community-list NAME {permit|deny} COMMUNITY
     When community list type is not specifed, the community list type
     is automatically detected.  If COMMUNITY can be compiled into
     communities attribute, the community list is defined as a standard
     community list.  Otherwise it is defined as an expanded community
     list.  This feature is left for backward compability.  Use of this
     feature is not recommended.

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File: quagga.info,  Node: BGP Community in Route Map,  Next: Display BGP Routes by Community,  Prev: Numbered BGP Community Lists,  Up: BGP Communities Attribute

11.9.3 BGP Community in Route Map
---------------------------------

In Route Map (*note Route Map::), we can match or set BGP communities
attribute.  Using this feature network operator can implement their
network policy based on BGP communities attribute.

   Following commands can be used in Route Map.

 -- Route Map: match community WORD
 -- Route Map: match community WORD exact-match
     This command perform match to BGP updates using community list
     WORD.  When the one of BGP communities value match to the one of
     communities value in community list, it is match.  When
     'exact-match' keyword is spcified, match happen only when BGP
     updates have completely same communities value specified in the
     community list.

 -- Route Map: set community none
 -- Route Map: set community COMMUNITY
 -- Route Map: set community COMMUNITY additive
     This command manipulate communities value in BGP updates.  When
     'none' is specified as communities value, it removes entire
     communities attribute from BGP updates.  When COMMUNITY is not
     'none', specified communities value is set to BGP updates.  If BGP
     updates already has BGP communities value, the existing BGP
     communities value is replaced with specified COMMUNITY value.  When
     'additive' keyword is specified, COMMUNITY is appended to the
     existing communities value.

 -- Route Map: set comm-list WORD delete
     This command remove communities value from BGP communities
     attribute.  The WORD is community list name.  When BGP route's
     communities value matches to the community list WORD, the
     communities value is removed.  When all of communities value is
     removed eventually, the BGP update's communities attribute is
     completely removed.

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File: quagga.info,  Node: Display BGP Routes by Community,  Next: Using BGP Communities Attribute,  Prev: BGP Community in Route Map,  Up: BGP Communities Attribute

11.9.4 Display BGP Routes by Community
--------------------------------------

To show BGP routes which has specific BGP communities attribute, 'show
ip bgp' command can be used.  The COMMUNITY value and community list can
be used for 'show ip bgp' command.

 -- Command: show ip bgp community
 -- Command: show ip bgp community COMMUNITY
 -- Command: show ip bgp community COMMUNITY exact-match
     'show ip bgp community' displays BGP routes which has communities
     attribute.  When COMMUNITY is specified, BGP routes that matches
     COMMUNITY value is displayed.  For this command, 'internet' keyword
     can't be used for COMMUNITY value.  When 'exact-match' is
     specified, it display only routes that have an exact match.

 -- Command: show ip bgp community-list WORD
 -- Command: show ip bgp community-list WORD exact-match
     This commands display BGP routes that matches community list WORD.
     When 'exact-match' is specified, display only routes that have an
     exact match.

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File: quagga.info,  Node: Using BGP Communities Attribute,  Prev: Display BGP Routes by Community,  Up: BGP Communities Attribute

11.9.5 Using BGP Communities Attribute
--------------------------------------

Following configuration is the most typical usage of BGP communities
attribute.  AS 7675 provides upstream Internet connection to AS 100.
When following configuration exists in AS 7675, AS 100 networks operator
can set local preference in AS 7675 network by setting BGP communities
attribute to the updates.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list 70 permit 7675:70
     ip community-list 70 deny
     ip community-list 80 permit 7675:80
     ip community-list 80 deny
     ip community-list 90 permit 7675:90
     ip community-list 90 deny
     !
     route-map RMAP permit 10
      match community 70
      set local-preference 70
     !
     route-map RMAP permit 20
      match community 80
      set local-preference 80
     !
     route-map RMAP permit 30
      match community 90
      set local-preference 90

   Following configuration announce 10.0.0.0/8 from AS 100 to AS 7675.
The route has communities value 7675:80 so when above configuration
exists in AS 7675, announced route's local preference will be set to
value 80.

     router bgp 100
      network 10.0.0.0/8
      neighbor 192.168.0.2 remote-as 7675
      neighbor 192.168.0.2 route-map RMAP out
     !
     ip prefix-list PLIST permit 10.0.0.0/8
     !
     route-map RMAP permit 10
      match ip address prefix-list PLIST
      set community 7675:80

   Following configuration is an example of BGP route filtering using
communities attribute.  This configuration only permit BGP routes which
has BGP communities value 0:80 and 0:90.  Network operator can put
special internal communities value at BGP border router, then limit the
BGP routes announcement into the internal network.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list 1 permit 0:80 0:90
     !
     route-map RMAP permit in
      match community 1

   Following exmaple filter BGP routes which has communities value 1:1.
When there is no match community-list returns deny.  To avoid filtering
all of routes, we need to define permit any at last.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list standard FILTER deny 1:1
     ip community-list standard FILTER permit
     !
     route-map RMAP permit 10
      match community FILTER

   Communities value keyword 'internet' has special meanings in standard
community lists.  In below example 'internet' act as match any.  It
matches all of BGP routes even if the route does not have communities
attribute at all.  So community list 'INTERNET' is same as above
example's 'FILTER'.

     ip community-list standard INTERNET deny 1:1
     ip community-list standard INTERNET permit internet

   Following configuration is an example of communities value deletion.
With this configuration communities value 100:1 and 100:2 is removed
from BGP updates.  For communities value deletion, only 'permit'
community-list is used.  'deny' community-list is ignored.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list standard DEL permit 100:1 100:2
     !
     route-map RMAP permit 10
      set comm-list DEL delete

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File: quagga.info,  Node: BGP Extended Communities Attribute,  Next: Displaying BGP routes,  Prev: BGP Communities Attribute,  Up: BGP

11.10 BGP Extended Communities Attribute
========================================

BGP extended communities attribute is introduced with MPLS VPN/BGP
technology.  MPLS VPN/BGP expands capability of network infrastructure
to provide VPN functionality.  At the same time it requires a new
framework for policy routing.  With BGP Extended Communities Attribute
we can use Route Target or Site of Origin for implementing network
policy for MPLS VPN/BGP.

   BGP Extended Communities Attribute is similar to BGP Communities
Attribute.  It is an optional transitive attribute.  BGP Extended
Communities Attribute can carry multiple Extended Community value.  Each
Extended Community value is eight octet length.

   BGP Extended Communities Attribute provides an extended range
compared with BGP Communities Attribute.  Adding to that there is a type
field in each value to provides community space structure.

   There are two format to define Extended Community value.  One is AS
based format the other is IP address based format.

'AS:VAL'
     This is a format to define AS based Extended Community value.  'AS'
     part is 2 octets Global Administrator subfield in Extended
     Community value.  'VAL' part is 4 octets Local Administrator
     subfield.  '7675:100' represents AS 7675 policy value 100.
'IP-Address:VAL'
     This is a format to define IP address based Extended Community
     value.  'IP-Address' part is 4 octets Global Administrator
     subfield.  'VAL' part is 2 octets Local Administrator subfield.
     '10.0.0.1:100' represents

* Menu:

* BGP Extended Community Lists::  
* BGP Extended Communities in Route Map::  

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File: quagga.info,  Node: BGP Extended Community Lists,  Next: BGP Extended Communities in Route Map,  Up: BGP Extended Communities Attribute

11.10.1 BGP Extended Community Lists
------------------------------------

Expanded Community Lists is a user defined BGP Expanded Community Lists.

 -- Command: ip extcommunity-list standard NAME {permit|deny}
          EXTCOMMUNITY
     This command defines a new standard extcommunity-list.
     EXTCOMMUNITY is extended communities value.  The EXTCOMMUNITY is
     compiled into extended community structure.  We can define multiple
     extcommunity-list under same name.  In that case match will happen
     user defined order.  Once the extcommunity-list matches to extended
     communities attribute in BGP updates it return permit or deny based
     upon the extcommunity-list definition.  When there is no matched
     entry, deny will be returned.  When EXTCOMMUNITY is empty it
     matches to any routes.

 -- Command: ip extcommunity-list expanded NAME {permit|deny} LINE
     This command defines a new expanded extcommunity-list.  LINE is a
     string expression of extended communities attribute.  LINE can
     include regular expression to match extended communities attribute
     in BGP updates.

 -- Command: no ip extcommunity-list NAME
 -- Command: no ip extcommunity-list standard NAME
 -- Command: no ip extcommunity-list expanded NAME
     These commands delete extended community lists specified by NAME.
     All of extended community lists shares a single name space.  So
     extended community lists can be removed simpley specifying the
     name.

 -- Command: show ip extcommunity-list
 -- Command: show ip extcommunity-list NAME
     This command display current extcommunity-list information.  When
     NAME is specified the community list's information is shown.

          # show ip extcommunity-list

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File: quagga.info,  Node: BGP Extended Communities in Route Map,  Prev: BGP Extended Community Lists,  Up: BGP Extended Communities Attribute

11.10.2 BGP Extended Communities in Route Map
---------------------------------------------

 -- Route Map: match extcommunity WORD

 -- Route Map: set extcommunity rt EXTCOMMUNITY
     This command set Route Target value.

 -- Route Map: set extcommunity soo EXTCOMMUNITY
     This command set Site of Origin value.

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File: quagga.info,  Node: Displaying BGP routes,  Next: Capability Negotiation,  Prev: BGP Extended Communities Attribute,  Up: BGP

11.11 Displaying BGP Routes
===========================

* Menu:

* Show IP BGP::                 
* More Show IP BGP::            

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File: quagga.info,  Node: Show IP BGP,  Next: More Show IP BGP,  Up: Displaying BGP routes

11.11.1 Show IP BGP
-------------------

 -- Command: show ip bgp
 -- Command: show ip bgp A.B.C.D
 -- Command: show ip bgp X:X::X:X
     This command displays BGP routes.  When no route is specified it
     display all of IPv4 BGP routes.

     BGP table version is 0, local router ID is 10.1.1.1
     Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
     Origin codes: i - IGP, e - EGP, ? - incomplete

        Network          Next Hop            Metric LocPrf Weight Path
     *> 1.1.1.1/32       0.0.0.0                  0         32768 i

     Total number of prefixes 1

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File: quagga.info,  Node: More Show IP BGP,  Prev: Show IP BGP,  Up: Displaying BGP routes

11.11.2 More Show IP BGP
------------------------

 -- Command: show ip bgp regexp LINE
     This command display BGP routes using AS path regular expression
     (*note Display BGP Routes by AS Path::).

 -- Command: show ip bgp community COMMUNITY
 -- Command: show ip bgp community COMMUNITY exact-match
     This command display BGP routes using COMMUNITY (*note Display BGP
     Routes by Community::).

 -- Command: show ip bgp community-list WORD
 -- Command: show ip bgp community-list WORD exact-match
     This command display BGP routes using community list (*note Display
     BGP Routes by Community::).

 -- Command: show ip bgp summary

 -- Command: show ip bgp neighbor [PEER]

 -- Command: clear ip bgp PEER
     Clear peers which have addresses of X.X.X.X

 -- Command: clear ip bgp PEER soft in
     Clear peer using soft reconfiguration.

 -- Command: show ip bgp dampened-paths
     Display paths suppressed due to dampening

 -- Command: show ip bgp flap-statistics
     Display flap statistics of routes

 -- Command: show debug

 -- Command: debug event

 -- Command: debug update

 -- Command: debug keepalive

 -- Command: no debug event

 -- Command: no debug update

 -- Command: no debug keepalive

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File: quagga.info,  Node: Capability Negotiation,  Next: Route Reflector,  Prev: Displaying BGP routes,  Up: BGP

11.12 Capability Negotiation
============================

When adding IPv6 routing information exchange feature to BGP. There were
some proposals.  IETF (Internet Engineering Task Force) IDR (Inter
Domain Routing) WG (Working group) adopted a proposal called
Multiprotocol Extension for BGP. The specification is described in
'RFC2283'.  The protocol does not define new protocols.  It defines new
attributes to existing BGP. When it is used exchanging IPv6 routing
information it is called BGP-4+.  When it is used for exchanging
multicast routing information it is called MBGP.

   'bgpd' supports Multiprotocol Extension for BGP. So if remote peer
supports the protocol, 'bgpd' can exchange IPv6 and/or multicast routing
information.

   Traditional BGP did not have the feature to detect remote peer's
capabilities, e.g.  whether it can handle prefix types other than IPv4
unicast routes.  This was a big problem using Multiprotocol Extension
for BGP to operational network.  'RFC2842, Capabilities Advertisement
with BGP-4' adopted a feature called Capability Negotiation.  'bgpd' use
this Capability Negotiation to detect the remote peer's capabilities.
If the peer is only configured as IPv4 unicast neighbor, 'bgpd' does not
send these Capability Negotiation packets (at least not unless other
optional BGP features require capability negotation).

   By default, Quagga will bring up peering with minimal common
capability for the both sides.  For example, local router has unicast
and multicast capabilitie and remote router has unicast capability.  In
this case, the local router will establish the connection with unicast
only capability.  When there are no common capabilities, Quagga sends
Unsupported Capability error and then resets the connection.

   If you want to completely match capabilities with remote peer.
Please use 'strict-capability-match' command.

 -- BGP: neighbor PEER strict-capability-match
 -- BGP: no neighbor PEER strict-capability-match
     Strictly compares remote capabilities and local capabilities.  If
     capabilities are different, send Unsupported Capability error then
     reset connection.

   You may want to disable sending Capability Negotiation OPEN message
optional parameter to the peer when remote peer does not implement
Capability Negotiation.  Please use 'dont-capability-negotiate' command
to disable the feature.

 -- BGP: neighbor PEER dont-capability-negotiate
 -- BGP: no neighbor PEER dont-capability-negotiate
     Suppress sending Capability Negotiation as OPEN message optional
     parameter to the peer.  This command only affects the peer is
     configured other than IPv4 unicast configuration.

   When remote peer does not have capability negotiation feature, remote
peer will not send any capabilities at all.  In that case, bgp
configures the peer with configured capabilities.

   You may prefer locally configured capabilities more than the
negotiated capabilities even though remote peer sends capabilities.  If
the peer is configured by 'override-capability', 'bgpd' ignores received
capabilities then override negotiated capabilities with configured
values.

 -- BGP: neighbor PEER override-capability
 -- BGP: no neighbor PEER override-capability
     Override the result of Capability Negotiation with local
     configuration.  Ignore remote peer's capability value.

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File: quagga.info,  Node: Route Reflector,  Next: Route Server,  Prev: Capability Negotiation,  Up: BGP

11.13 Route Reflector
=====================

 -- BGP: bgp cluster-id A.B.C.D

 -- BGP: neighbor PEER route-reflector-client
 -- BGP: no neighbor PEER route-reflector-client

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File: quagga.info,  Node: Route Server,  Next: How to set up a 6-Bone connection,  Prev: Route Reflector,  Up: BGP

11.14 Route Server
==================

At an Internet Exchange point, many ISPs are connected to each other by
external BGP peering.  Normally these external BGP connection are done
by 'full mesh' method.  As with internal BGP full mesh formation, this
method has a scaling problem.

   This scaling problem is well known.  Route Server is a method to
resolve the problem.  Each ISP's BGP router only peers to Route Server.
Route Server serves as BGP information exchange to other BGP routers.
By applying this method, numbers of BGP connections is reduced from
O(n*(n-1)/2) to O(n).

   Unlike normal BGP router, Route Server must have several routing
tables for managing different routing policies for each BGP speaker.  We
call the routing tables as different 'view's.  'bgpd' can work as normal
BGP router or Route Server or both at the same time.

* Menu:

* Multiple instance::           
* BGP instance and view::       
* Routing policy::              
* Viewing the view::            

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File: quagga.info,  Node: Multiple instance,  Next: BGP instance and view,  Up: Route Server

11.14.1 Multiple instance
-------------------------

To enable multiple view function of 'bgpd', you must turn on multiple
instance feature beforehand.

 -- Command: bgp multiple-instance
     Enable BGP multiple instance feature.  After this feature is
     enabled, you can make multiple BGP instances or multiple BGP views.

 -- Command: no bgp multiple-instance
     Disable BGP multiple instance feature.  You can not disable this
     feature when BGP multiple instances or views exist.

   When you want to make configuration more Cisco like one,

 -- Command: bgp config-type cisco
     Cisco compatible BGP configuration output.

   When bgp config-type cisco is specified,

   "no synchronization" is displayed.  "no auto-summary" is displayed.

   "network" and "aggregate-address" argument is displayed as "A.B.C.D
M.M.M.M"

   Quagga: network 10.0.0.0/8 Cisco: network 10.0.0.0

   Quagga: aggregate-address 192.168.0.0/24 Cisco: aggregate-address
192.168.0.0 255.255.255.0

   Community attribute handling is also different.  If there is no
configuration is specified community attribute and extended community
attribute are sent to neighbor.  When user manually disable the feature
community attribute is not sent to the neighbor.  In case of 'bgp
config-type cisco' is specified, community attribute is not sent to the
neighbor by default.  To send community attribute user has to specify
'neighbor A.B.C.D send-community' command.

     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 1
      no neighbor 10.0.0.1 send-community
     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 1
      neighbor 10.0.0.1 send-community
     !

 -- Command: bgp config-type zebra
     Quagga style BGP configuration.  This is default.

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File: quagga.info,  Node: BGP instance and view,  Next: Routing policy,  Prev: Multiple instance,  Up: Route Server

11.14.2 BGP instance and view
-----------------------------

BGP instance is a normal BGP process.  The result of route selection
goes to the kernel routing table.  You can setup different AS at the
same time when BGP multiple instance feature is enabled.

 -- Command: router bgp AS-NUMBER
     Make a new BGP instance.  You can use arbitrary word for the NAME.

     bgp multiple-instance
     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.2 remote-as 3
     !
     router bgp 2
      neighbor 10.0.0.3 remote-as 4
      neighbor 10.0.0.4 remote-as 5

   BGP view is almost same as normal BGP process.  The result of route
selection does not go to the kernel routing table.  BGP view is only for
exchanging BGP routing information.

 -- Command: router bgp AS-NUMBER view NAME
     Make a new BGP view.  You can use arbitrary word for the NAME.
     This view's route selection result does not go to the kernel
     routing table.

   With this command, you can setup Route Server like below.

     bgp multiple-instance
     !
     router bgp 1 view 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.2 remote-as 3
     !
     router bgp 2 view 2
      neighbor 10.0.0.3 remote-as 4
      neighbor 10.0.0.4 remote-as 5

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File: quagga.info,  Node: Routing policy,  Next: Viewing the view,  Prev: BGP instance and view,  Up: Route Server

11.14.3 Routing policy
----------------------

You can set different routing policy for a peer.  For example, you can
set different filter for a peer.

     bgp multiple-instance
     !
     router bgp 1 view 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.1 distribute-list 1 in
     !
     router bgp 1 view 2
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.1 distribute-list 2 in

   This means BGP update from a peer 10.0.0.1 goes to both BGP view 1
and view 2.  When the update is inserted into view 1, distribute-list 1
is applied.  On the other hand, when the update is inserted into view 2,
distribute-list 2 is applied.

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File: quagga.info,  Node: Viewing the view,  Prev: Routing policy,  Up: Route Server

11.14.4 Viewing the view
------------------------

To display routing table of BGP view, you must specify view name.

 -- Command: show ip bgp view NAME
     Display routing table of BGP view NAME.

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File: quagga.info,  Node: How to set up a 6-Bone connection,  Next: Dump BGP packets and table,  Prev: Route Server,  Up: BGP

11.15 How to set up a 6-Bone connection
=======================================

     zebra configuration
     ===================
     !
     ! Actually there is no need to configure zebra
     !

     bgpd configuration
     ==================
     !
     ! This means that routes go through zebra and into the kernel.
     !
     router zebra
     !
     ! MP-BGP configuration
     !
     router bgp 7675
      bgp router-id 10.0.0.1
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 remote-as AS-NUMBER
     !
      address-family ipv6
      network 3ffe:506::/32
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 activate
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 route-map set-nexthop out
      neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 remote-as AS-NUMBER
      neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 route-map set-nexthop out
      exit-address-family
     !
     ipv6 access-list all permit any
     !
     ! Set output nexthop address.
     !
     route-map set-nexthop permit 10
      match ipv6 address all
      set ipv6 nexthop global 3ffe:1cfa:0:2:2c0:4fff:fe68:a225
      set ipv6 nexthop local fe80::2c0:4fff:fe68:a225
     !
     ! logfile FILENAME is obsolete.  Please use log file FILENAME

     log file bgpd.log
     !

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File: quagga.info,  Node: Dump BGP packets and table,  Next: BGP Configuration Examples,  Prev: How to set up a 6-Bone connection,  Up: BGP

11.16 Dump BGP packets and table
================================

 -- Command: dump bgp all PATH [INTERVAL]
 -- Command: dump bgp all-et PATH [INTERVAL]
 -- Command: no dump bgp all [PATH] [INTERVAL]
     Dump all BGP packet and events to PATH file.  If INTERVAL is set, a
     new file will be created for echo INTERVAL of seconds.  The path
     PATH can be set with date and time formatting (strftime).  The type
     ‘all-et’ enables support for Extended Timestamp Header (*note
     Packet Binary Dump Format::).  (*note Packet Binary Dump Format::)

 -- Command: dump bgp updates PATH [INTERVAL]
 -- Command: dump bgp updates-et PATH [INTERVAL]
 -- Command: no dump bgp updates [PATH] [INTERVAL]
     Dump only BGP updates messages to PATH file.  If INTERVAL is set, a
     new file will be created for echo INTERVAL of seconds.  The path
     PATH can be set with date and time formatting (strftime).  The type
     ‘updates-et’ enables support for Extended Timestamp Header
     (*note Packet Binary Dump Format::).

 -- Command: dump bgp routes-mrt PATH
 -- Command: dump bgp routes-mrt PATH INTERVAL
 -- Command: no dump bgp route-mrt [PATH] [INTERVAL]
     Dump whole BGP routing table to PATH.  This is heavy process.  The
     path PATH can be set with date and time formatting (strftime).  If
     INTERVAL is set, a new file will be created for echo INTERVAL of
     seconds.

   Note: the interval variable can also be set using hours and minutes:
04h20m00.

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File: quagga.info,  Node: BGP Configuration Examples,  Prev: Dump BGP packets and table,  Up: BGP

11.17 BGP Configuration Examples
================================

Example of a session to an upstream, advertising only one prefix to it.

     router bgp 64512
      bgp router-id 10.236.87.1
      network 10.236.87.0/24
      neighbor upstream peer-group
      neighbor upstream remote-as 64515
      neighbor upstream capability dynamic
      neighbor upstream prefix-list pl-allowed-adv out
      neighbor 10.1.1.1 peer-group upstream
      neighbor 10.1.1.1 description ACME ISP
     !
     ip prefix-list pl-allowed-adv seq 5 permit 82.195.133.0/25
     ip prefix-list pl-allowed-adv seq 10 deny any


   A more complex example.  With upstream, peer and customer sessions.
Advertising global prefixes and NO_EXPORT prefixes and providing actions
for customer routes based on community values.  Extensive use of
route-maps and the 'call' feature to support selective advertising of
prefixes.  This example is intended as guidance only, it has NOT been
tested and almost certainly containts silly mistakes, if not serious
flaws.

     router bgp 64512
      bgp router-id 10.236.87.1
      network 10.123.456.0/24
      network 10.123.456.128/25 route-map rm-no-export
      neighbor upstream capability dynamic
      neighbor upstream route-map rm-upstream-out out
      neighbor cust capability dynamic
      neighbor cust route-map rm-cust-in in
      neighbor cust route-map rm-cust-out out
      neighbor cust send-community both
      neighbor peer capability dynamic
      neighbor peer route-map rm-peer-in in
      neighbor peer route-map rm-peer-out out
      neighbor peer send-community both
      neighbor 10.1.1.1 remote-as 64515
      neighbor 10.1.1.1 peer-group upstream
      neighbor 10.2.1.1 remote-as 64516
      neighbor 10.2.1.1 peer-group upstream
      neighbor 10.3.1.1 remote-as 64517
      neighbor 10.3.1.1 peer-group cust-default
      neighbor 10.3.1.1 description customer1
      neighbor 10.3.1.1 prefix-list pl-cust1-network in
      neighbor 10.4.1.1 remote-as 64518
      neighbor 10.4.1.1 peer-group cust
      neighbor 10.4.1.1 prefix-list pl-cust2-network in
      neighbor 10.4.1.1 description customer2
      neighbor 10.5.1.1 remote-as 64519
      neighbor 10.5.1.1 peer-group peer
      neighbor 10.5.1.1 prefix-list pl-peer1-network in
      neighbor 10.5.1.1 description peer AS 1
      neighbor 10.6.1.1 remote-as 64520
      neighbor 10.6.1.1 peer-group peer
      neighbor 10.6.1.1 prefix-list pl-peer2-network in
      neighbor 10.6.1.1 description peer AS 2
     !
     ip prefix-list pl-default permit 0.0.0.0/0
     !
     ip prefix-list pl-upstream-peers permit 10.1.1.1/32
     ip prefix-list pl-upstream-peers permit 10.2.1.1/32
     !
     ip prefix-list pl-cust1-network permit 10.3.1.0/24
     ip prefix-list pl-cust1-network permit 10.3.2.0/24
     !
     ip prefix-list pl-cust2-network permit 10.4.1.0/24
     !
     ip prefix-list pl-peer1-network permit 10.5.1.0/24
     ip prefix-list pl-peer1-network permit 10.5.2.0/24
     ip prefix-list pl-peer1-network permit 192.168.0.0/24
     !
     ip prefix-list pl-peer2-network permit 10.6.1.0/24
     ip prefix-list pl-peer2-network permit 10.6.2.0/24
     ip prefix-list pl-peer2-network permit 192.168.1.0/24
     ip prefix-list pl-peer2-network permit 192.168.2.0/24
     ip prefix-list pl-peer2-network permit 172.16.1/24
     !
     ip as-path access-list asp-own-as permit ^$
     ip as-path access-list asp-own-as permit _64512_
     !
     ! #################################################################
     ! Match communities we provide actions for, on routes receives from
     ! customers. Communities values of <our-ASN>:X, with X, have actions:
     !
     ! 100 - blackhole the prefix
     ! 200 - set no_export
     ! 300 - advertise only to other customers
     ! 400 - advertise only to upstreams
     ! 500 - set no_export when advertising to upstreams
     ! 2X00 - set local_preference to X00
     !
     ! blackhole the prefix of the route
     ip community-list standard cm-blackhole permit 64512:100
     !
     ! set no-export community before advertising
     ip community-list standard cm-set-no-export permit 64512:200
     !
     ! advertise only to other customers
     ip community-list standard cm-cust-only permit 64512:300
     !
     ! advertise only to upstreams
     ip community-list standard cm-upstream-only permit 64512:400
     !
     ! advertise to upstreams with no-export
     ip community-list standard cm-upstream-noexport permit 64512:500
     !
     ! set local-pref to least significant 3 digits of the community
     ip community-list standard cm-prefmod-100 permit 64512:2100
     ip community-list standard cm-prefmod-200 permit 64512:2200
     ip community-list standard cm-prefmod-300 permit 64512:2300
     ip community-list standard cm-prefmod-400 permit 64512:2400
     ip community-list expanded cme-prefmod-range permit 64512:2...
     !
     ! Informational communities
     !
     ! 3000 - learned from upstream
     ! 3100 - learned from customer
     ! 3200 - learned from peer
     !
     ip community-list standard cm-learnt-upstream permit 64512:3000
     ip community-list standard cm-learnt-cust permit 64512:3100
     ip community-list standard cm-learnt-peer permit 64512:3200
     !
     ! ###################################################################
     ! Utility route-maps
     !
     ! These utility route-maps generally should not used to permit/deny
     ! routes, i.e. they do not have meaning as filters, and hence probably
     ! should be used with 'on-match next'. These all finish with an empty
     ! permit entry so as not interfere with processing in the caller.
     !
     route-map rm-no-export permit 10
      set community additive no-export
     route-map rm-no-export permit 20
     !
     route-map rm-blackhole permit 10
      description blackhole, up-pref and ensure it cant escape this AS
      set ip next-hop 127.0.0.1
      set local-preference 10
      set community additive no-export
     route-map rm-blackhole permit 20
     !
     ! Set local-pref as requested
     route-map rm-prefmod permit 10
      match community cm-prefmod-100
      set local-preference 100
     route-map rm-prefmod permit 20
      match community cm-prefmod-200
      set local-preference 200
     route-map rm-prefmod permit 30
      match community cm-prefmod-300
      set local-preference 300
     route-map rm-prefmod permit 40
      match community cm-prefmod-400
      set local-preference 400
     route-map rm-prefmod permit 50
     !
     ! Community actions to take on receipt of route.
     route-map rm-community-in permit 10
      description check for blackholing, no point continuing if it matches.
      match community cm-blackhole
      call rm-blackhole
     route-map rm-community-in permit 20
      match community cm-set-no-export
      call rm-no-export
      on-match next
     route-map rm-community-in permit 30
      match community cme-prefmod-range
      call rm-prefmod
     route-map rm-community-in permit 40
     !
     ! #####################################################################
     ! Community actions to take when advertising a route.
     ! These are filtering route-maps,
     !
     ! Deny customer routes to upstream with cust-only set.
     route-map rm-community-filt-to-upstream deny 10
      match community cm-learnt-cust
      match community cm-cust-only
     route-map rm-community-filt-to-upstream permit 20
     !
     ! Deny customer routes to other customers with upstream-only set.
     route-map rm-community-filt-to-cust deny 10
      match community cm-learnt-cust
      match community cm-upstream-only
     route-map rm-community-filt-to-cust permit 20
     !
     ! ###################################################################
     ! The top-level route-maps applied to sessions. Further entries could
     ! be added obviously..
     !
     ! Customers
     route-map rm-cust-in permit 10
      call rm-community-in
      on-match next
     route-map rm-cust-in permit 20
      set community additive 64512:3100
     route-map rm-cust-in permit 30
     !
     route-map rm-cust-out permit 10
      call rm-community-filt-to-cust
      on-match next
     route-map rm-cust-out permit 20
     !
     ! Upstream transit ASes
     route-map rm-upstream-out permit 10
      description filter customer prefixes which are marked cust-only
      call rm-community-filt-to-upstream
      on-match next
     route-map rm-upstream-out permit 20
      description only customer routes are provided to upstreams/peers
      match community cm-learnt-cust
     !
     ! Peer ASes
     ! outbound policy is same as for upstream
     route-map rm-peer-out permit 10
      call rm-upstream-out
     !
     route-map rm-peer-in permit 10
      set community additive 64512:3200

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File: quagga.info,  Node: Configuring Quagga as a Route Server,  Next: VTY shell,  Prev: BGP,  Up: Top

12 Configuring Quagga as a Route Server
***************************************

The purpose of a Route Server is to centralize the peerings between BGP
speakers.  For example if we have an exchange point scenario with four
BGP speakers, each of which maintaining a BGP peering with the other
three we can convert it into a centralized scenario where each of the
four establishes a single BGP peering against the Route Server.

   We will first describe briefly the Route Server model implemented by
Quagga.  We will explain the commands that have been added for
configuring that model.  And finally we will show a full example of
Quagga configured as Route Server.

* Menu:

* Description of the Route Server model::
* Commands for configuring a Route Server::
* Example of Route Server Configuration::

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File: quagga.info,  Node: Description of the Route Server model,  Next: Commands for configuring a Route Server,  Up: Configuring Quagga as a Route Server

12.1 Description of the Route Server model
==========================================

First we are going to describe the normal processing that BGP
announcements suffer inside a standard BGP speaker, as shown in *note
Figure 12.1: fig:normal-processing, it consists of three steps:

   * When an announcement is received from some peer, the 'In' filters
     configured for that peer are applied to the announcement.  These
     filters can reject the announcement, accept it unmodified, or
     accept it with some of its attributes modified.

   * The announcements that pass the 'In' filters go into the Best Path
     Selection process, where they are compared to other announcements
     referred to the same destination that have been received from
     different peers (in case such other announcements exist).  For each
     different destination, the announcement which is selected as the
     best is inserted into the BGP speaker's Loc-RIB.

   * The routes which are inserted in the Loc-RIB are considered for
     announcement to all the peers (except the one from which the route
     came).  This is done by passing the routes in the Loc-RIB through
     the 'Out' filters corresponding to each peer.  These filters can
     reject the route, accept it unmodified, or accept it with some of
     its attributes modified.  Those routes which are accepted by the
     'Out' filters of a peer are announced to that peer.

\0\b[image src="fig-normal-processing.png" alt="Normal announcement processing" text="
                  _______________________________
                 /    _________     _________    \\
From Peer A --->|(A)-|Best     |   |         |-[A]|--->To Peer A
From Peer B --->|(B)-|Path     |-->|Local-RIB|-[B]|--->To Peer B
From Peer C --->|(C)-|Selection|   |         |-[C]|--->To Peer C
From Peer D --->|(D)-|_________|   |_________|-[D]|--->To Peer D
                 \\_______________________________/

Key:  (X) - 'In'  Filter applied to Peer X's announcements
      [X] - 'Out' Filter applied to announcements to Peer X"\0\b]

Figure 12.1: Announcement processing inside a "normal" BGP speaker

   Of course we want that the routing tables obtained in each of the
routers are the same when using the route server than when not.  But as
a consequence of having a single BGP peering (against the route server),
the BGP speakers can no longer distinguish from/to which peer each
announce comes/goes.  This means that the routers connected to the route
server are not able to apply by themselves the same input/output filters
as in the full mesh scenario, so they have to delegate those functions
to the route server.

   Even more, the "best path" selection must be also performed inside
the route server on behalf of its clients.  The reason is that if, after
applying the filters of the announcer and the (potential) receiver, the
route server decides to send to some client two or more different
announcements referred to the same destination, the client will only
retain the last one, considering it as an implicit withdrawal of the
previous announcements for the same destination.  This is the expected
behavior of a BGP speaker as defined in 'RFC1771', and even though there
are some proposals of mechanisms that permit multiple paths for the same
destination to be sent through a single BGP peering, none are currently
supported by most existing BGP implementations.

   As a consequence a route server must maintain additional information
and perform additional tasks for a RS-client that those necessary for
common BGP peerings.  Essentially a route server must:

   * Maintain a separated Routing Information Base (Loc-RIB) for each
     peer configured as RS-client, containing the routes selected as a
     result of the "Best Path Selection" process that is performed on
     behalf of that RS-client.

   * Whenever it receives an announcement from a RS-client, it must
     consider it for the Loc-RIBs of the other RS-clients.

        * This means that for each of them the route server must pass
          the announcement through the appropriate 'Out' filter of the
          announcer.

        * Then through the appropriate 'In' filter of the potential
          receiver.

        * Only if the announcement is accepted by both filters it will
          be passed to the "Best Path Selection" process.

        * Finally, it might go into the Loc-RIB of the receiver.

   When we talk about the "appropriate" filter, both the announcer and
the receiver of the route must be taken into account.  Suppose that the
route server receives an announcement from client A, and the route
server is considering it for the Loc-RIB of client B. The filters that
should be applied are the same that would be used in the full mesh
scenario, i.e., first the 'Out' filter of router A for announcements
going to router B, and then the 'In' filter of router B for
announcements coming from router A.

   We call "Export Policy" of a RS-client to the set of 'Out' filters
that the client would use if there was no route server.  The same
applies for the "Import Policy" of a RS-client and the set of 'In'
filters of the client if there was no route server.

   It is also common to demand from a route server that it does not
modify some BGP attributes (next-hop, as-path and MED) that are usually
modified by standard BGP speakers before announcing a route.

   The announcement processing model implemented by Quagga is shown in
*note Figure 12.2: fig:rs-processing.  The figure shows a mixture of
RS-clients (B, C and D) with normal BGP peers (A). There are some
details that worth additional comments:

   * Announcements coming from a normal BGP peer are also considered for
     the Loc-RIBs of all the RS-clients.  But logically they do not pass
     through any export policy.

   * Those peers that are configured as RS-clients do not receive any
     announce from the 'Main' Loc-RIB.

   * Apart from import and export policies, 'In' and 'Out' filters can
     also be set for RS-clients.  'In' filters might be useful when the
     route server has also normal BGP peers.  On the other hand, 'Out'
     filters for RS-clients are probably unnecessary, but we decided not
     to remove them as they do not hurt anybody (they can always be left
     empty).

\0\b[image src="fig-rs-processing.png" alt="Route Server Processing Model" text="From Peer A
 | From RS-Client B
 |  | From RS-Client C
 |  |  | From RS-Client D
 |  |  |  |
 |  |  |  |           Main / Normal RIB
 |  |  |  |      ________________________________
 |  |  |  |     /    _________     _________     \\
 |  |  |  +--->|(D)-|Best     |   | Main    |     |
 |  |  +--|--->|(C)-|Path     |-->|Local-RIB|->[A]|--->To Peer A
 |  +--|--|--->|(B)-|Selection|   |         |     |
 +--|--|--|--->|(A)-|_________|   |_________|     |
 |  |  |  |     \\________________________________/
 |  |  |  |
 |  |  |  |          ________________________________
 |  |  |  |          /    _________     _________     \\
 |  |  |  +--->*D*->|{B}-|Best     |   |RS-Client|     |
 |  |  +--|--->*C*->|{B}-|Path     |-->|Local-RIB|->[B]|--->To RS-Client B
 |  |  |  |         |    |Selection|   |  for B  |     |
 +--|--|--|-------->|{B}-|_________|   |_________|     |
 |  |  |  |          \\________________________________/
 |  |  |  |
 |  |  |  |          ________________________________
 |  |  |  |          /    _________     _________     \\
 |  |  |  +--->*D*->|{C}-|Best     |   |RS-Client|     |
 |  |  |  |         |    |Path     |-->|Local-RIB|->[C]|--->To RS-Client C
 |  +--|--|--->*B*->|{C}-|Selection|   |  for C  |     |
 +--|--|--|-------->|{C}-|_________|   |_________|     |
 |  |  |             \\________________________________/
 |  |  |
 |  |  |              ________________________________
 |  |  |             /    _________     _________     \\
 |  |  |            |    |Best     |   |RS-Client|     |
 |  |  +------>*C*->|{D}-|Path     |-->|Local-RIB|->[D]|--->To RS-Client D
 |  +--------->*B*->|{D}-|Selection|   |  for D  |     |
 +----------------->|{D}-|_________|   |_________|     |
                     \\________________________________/


Key:  (X) - 'In'  Filter applied to Peer X's announcements before
            considering announcement for the normal main Local-RIB
      [X] - 'Out' Filter applied to announcements to Peer X
      *X* - 'Export' Filter of RS-Client X, to apply X's policies
            before its routes may be considered for other RS-Clients
            RIBs.
      {X} - 'Import' Filter of RS-Client X, to apply X's policies
            on routes before allowing them into X's RIB."\0\b]

Figure 12.2: Announcement processing model implemented by the Route
Server

\1f
File: quagga.info,  Node: Commands for configuring a Route Server,  Next: Example of Route Server Configuration,  Prev: Description of the Route Server model,  Up: Configuring Quagga as a Route Server

12.2 Commands for configuring a Route Server
============================================

Now we will describe the commands that have been added to quagga in
order to support the route server features.

 -- Route-Server: neighbor PEER-GROUP route-server-client
 -- Route-Server: neighbor A.B.C.D route-server-client
 -- Route-Server: neighbor X:X::X:X route-server-client
     This command configures the peer given by PEER, A.B.C.D or X:X::X:X
     as an RS-client.

     Actually this command is not new, it already existed in standard
     Quagga.  It enables the transparent mode for the specified peer.
     This means that some BGP attributes (as-path, next-hop and MED) of
     the routes announced to that peer are not modified.

     With the route server patch, this command, apart from setting the
     transparent mode, creates a new Loc-RIB dedicated to the specified
     peer (those named 'Loc-RIB for X' in *note Figure 12.2:
     fig:rs-processing.).  Starting from that moment, every announcement
     received by the route server will be also considered for the new
     Loc-RIB.

 -- Route-Server: neigbor {A.B.C.D|X.X::X.X|peer-group} route-map WORD
          {import|export}
     This set of commands can be used to specify the route-map that
     represents the Import or Export policy of a peer which is
     configured as a RS-client (with the previous command).

 -- Route-Server: match peer {A.B.C.D|X:X::X:X}
     This is a new _match_ statement for use in route-maps, enabling
     them to describe import/export policies.  As we said before, an
     import/export policy represents a set of input/output filters of
     the RS-client.  This statement makes possible that a single
     route-map represents the full set of filters that a BGP speaker
     would use for its different peers in a non-RS scenario.

     The _match peer_ statement has different semantics whether it is
     used inside an import or an export route-map.  In the first case
     the statement matches if the address of the peer who sends the
     announce is the same that the address specified by
     {A.B.C.D|X:X::X:X}.  For export route-maps it matches when
     {A.B.C.D|X:X::X:X} is the address of the RS-Client into whose
     Loc-RIB the announce is going to be inserted (how the same export
     policy is applied before different Loc-RIBs is shown in *note
     Figure 12.2: fig:rs-processing.).

 -- Route-map Command: call WORD
     This command (also used inside a route-map) jumps into a different
     route-map, whose name is specified by WORD.  When the called
     route-map finishes, depending on its result the original route-map
     continues or not.  Apart from being useful for making import/export
     route-maps easier to write, this command can also be used inside
     any normal (in or out) route-map.

\1f
File: quagga.info,  Node: Example of Route Server Configuration,  Prev: Commands for configuring a Route Server,  Up: Configuring Quagga as a Route Server

12.3 Example of Route Server Configuration
==========================================

Finally we are going to show how to configure a Quagga daemon to act as
a Route Server.  For this purpose we are going to present a scenario
without route server, and then we will show how to use the
configurations of the BGP routers to generate the configuration of the
route server.

   All the configuration files shown in this section have been taken
from scenarios which were tested using the VNUML tool VNUML
(http://www.dit.upm.es/vnuml).

* Menu:

* Configuration of the BGP routers without Route Server::
* Configuration of the BGP routers with Route Server::
* Configuration of the Route Server itself::
* Further considerations about Import and Export route-maps::

\1f
File: quagga.info,  Node: Configuration of the BGP routers without Route Server,  Next: Configuration of the BGP routers with Route Server,  Up: Example of Route Server Configuration

12.3.1 Configuration of the BGP routers without Route Server
------------------------------------------------------------

We will suppose that our initial scenario is an exchange point with
three BGP capable routers, named RA, RB and RC. Each of the BGP speakers
generates some routes (with the NETWORK command), and establishes BGP
peerings against the other two routers.  These peerings have In and Out
route-maps configured, named like "PEER-X-IN" or "PEER-X-OUT". For
example the configuration file for router RA could be the following:

     #Configuration for router 'RA'
     !
     hostname RA
     password ****
     !
     router bgp 65001
       no bgp default ipv4-unicast
       neighbor 2001:0DB8::B remote-as 65002
       neighbor 2001:0DB8::C remote-as 65003
     !
       address-family ipv6
         network 2001:0DB8:AAAA:1::/64
         network 2001:0DB8:AAAA:2::/64
         network 2001:0DB8:0000:1::/64
         network 2001:0DB8:0000:2::/64

         neighbor 2001:0DB8::B activate
         neighbor 2001:0DB8::B soft-reconfiguration inbound
         neighbor 2001:0DB8::B route-map PEER-B-IN in
         neighbor 2001:0DB8::B route-map PEER-B-OUT out

         neighbor 2001:0DB8::C activate
         neighbor 2001:0DB8::C soft-reconfiguration inbound
         neighbor 2001:0DB8::C route-map PEER-C-IN in
         neighbor 2001:0DB8::C route-map PEER-C-OUT out
       exit-address-family
     !
     ipv6 prefix-list COMMON-PREFIXES seq  5 permit 2001:0DB8:0000::/48 ge 64 le 64
     ipv6 prefix-list COMMON-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-A-PREFIXES seq  5 permit 2001:0DB8:AAAA::/48 ge 64 le 64
     ipv6 prefix-list PEER-A-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-B-PREFIXES seq  5 permit 2001:0DB8:BBBB::/48 ge 64 le 64
     ipv6 prefix-list PEER-B-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-C-PREFIXES seq  5 permit 2001:0DB8:CCCC::/48 ge 64 le 64
     ipv6 prefix-list PEER-C-PREFIXES seq 10 deny any
     !
     route-map PEER-B-IN permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set metric 100
     route-map PEER-B-IN permit 20
       match ipv6 address prefix-list PEER-B-PREFIXES
       set community 65001:11111
     !
     route-map PEER-C-IN permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set metric 200
     route-map PEER-C-IN permit 20
       match ipv6 address prefix-list PEER-C-PREFIXES
       set community 65001:22222
     !
     route-map PEER-B-OUT permit 10
       match ipv6 address prefix-list PEER-A-PREFIXES
     !
     route-map PEER-C-OUT permit 10
       match ipv6 address prefix-list PEER-A-PREFIXES
     !
     line vty
     !

\1f
File: quagga.info,  Node: Configuration of the BGP routers with Route Server,  Next: Configuration of the Route Server itself,  Prev: Configuration of the BGP routers without Route Server,  Up: Example of Route Server Configuration

12.3.2 Configuration of the BGP routers with Route Server
---------------------------------------------------------

To convert the initial scenario into one with route server, first we
must modify the configuration of routers RA, RB and RC. Now they must
not peer between them, but only with the route server.  For example,
RA's configuration would turn into:

     # Configuration for router 'RA'
     !
     hostname RA
     password ****
     !
     router bgp 65001
       no bgp default ipv4-unicast
       neighbor 2001:0DB8::FFFF remote-as 65000
     !
       address-family ipv6
         network 2001:0DB8:AAAA:1::/64
         network 2001:0DB8:AAAA:2::/64
         network 2001:0DB8:0000:1::/64
         network 2001:0DB8:0000:2::/64

         neighbor 2001:0DB8::FFFF activate
         neighbor 2001:0DB8::FFFF soft-reconfiguration inbound
       exit-address-family
     !
     line vty
     !

   Which is logically much simpler than its initial configuration, as it
now maintains only one BGP peering and all the filters (route-maps) have
disappeared.

\1f
File: quagga.info,  Node: Configuration of the Route Server itself,  Next: Further considerations about Import and Export route-maps,  Prev: Configuration of the BGP routers with Route Server,  Up: Example of Route Server Configuration

12.3.3 Configuration of the Route Server itself
-----------------------------------------------

As we said when we described the functions of a route server (*note
Description of the Route Server model::), it is in charge of all the
route filtering.  To achieve that, the In and Out filters from the RA,
RB and RC configurations must be converted into Import and Export
policies in the route server.

   This is a fragment of the route server configuration (we only show
the policies for client RA):

     # Configuration for Route Server ('RS')
     !
     hostname RS
     password ix
     !
     bgp multiple-instance
     !
     router bgp 65000 view RS
       no bgp default ipv4-unicast
       neighbor 2001:0DB8::A  remote-as 65001
       neighbor 2001:0DB8::B  remote-as 65002
       neighbor 2001:0DB8::C  remote-as 65003
     !
       address-family ipv6
         neighbor 2001:0DB8::A activate
         neighbor 2001:0DB8::A route-server-client
         neighbor 2001:0DB8::A route-map RSCLIENT-A-IMPORT import
         neighbor 2001:0DB8::A route-map RSCLIENT-A-EXPORT export
         neighbor 2001:0DB8::A soft-reconfiguration inbound

         neighbor 2001:0DB8::B activate
         neighbor 2001:0DB8::B route-server-client
         neighbor 2001:0DB8::B route-map RSCLIENT-B-IMPORT import
         neighbor 2001:0DB8::B route-map RSCLIENT-B-EXPORT export
         neighbor 2001:0DB8::B soft-reconfiguration inbound

         neighbor 2001:0DB8::C activate
         neighbor 2001:0DB8::C route-server-client
         neighbor 2001:0DB8::C route-map RSCLIENT-C-IMPORT import
         neighbor 2001:0DB8::C route-map RSCLIENT-C-EXPORT export
         neighbor 2001:0DB8::C soft-reconfiguration inbound
       exit-address-family
     !
     ipv6 prefix-list COMMON-PREFIXES seq  5 permit 2001:0DB8:0000::/48 ge 64 le 64
     ipv6 prefix-list COMMON-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-A-PREFIXES seq  5 permit 2001:0DB8:AAAA::/48 ge 64 le 64
     ipv6 prefix-list PEER-A-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-B-PREFIXES seq  5 permit 2001:0DB8:BBBB::/48 ge 64 le 64
     ipv6 prefix-list PEER-B-PREFIXES seq 10 deny any
     !
     ipv6 prefix-list PEER-C-PREFIXES seq  5 permit 2001:0DB8:CCCC::/48 ge 64 le 64
     ipv6 prefix-list PEER-C-PREFIXES seq 10 deny any
     !
     route-map RSCLIENT-A-IMPORT permit 10
       match peer 2001:0DB8::B
       call A-IMPORT-FROM-B
     route-map RSCLIENT-A-IMPORT permit 20
       match peer 2001:0DB8::C
       call A-IMPORT-FROM-C
     !
     route-map A-IMPORT-FROM-B permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set metric 100
     route-map A-IMPORT-FROM-B permit 20
       match ipv6 address prefix-list PEER-B-PREFIXES
       set community 65001:11111
     !
     route-map A-IMPORT-FROM-C permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set metric 200
     route-map A-IMPORT-FROM-C permit 20
       match ipv6 address prefix-list PEER-C-PREFIXES
       set community 65001:22222
     !
     route-map RSCLIENT-A-EXPORT permit 10
       match peer 2001:0DB8::B
       match ipv6 address prefix-list PEER-A-PREFIXES
     route-map RSCLIENT-A-EXPORT permit 20
       match peer 2001:0DB8::C
       match ipv6 address prefix-list PEER-A-PREFIXES
     !
     ...
     ...
     ...

   If you compare the initial configuration of RA with the route server
configuration above, you can see how easy it is to generate the Import
and Export policies for RA from the In and Out route-maps of RA's
original configuration.

   When there was no route server, RA maintained two peerings, one with
RB and another with RC. Each of this peerings had an In route-map
configured.  To build the Import route-map for client RA in the route
server, simply add route-map entries following this scheme:

     route-map <NAME> permit 10
         match peer <Peer Address>
         call <In Route-Map for this Peer>
     route-map <NAME> permit 20
         match peer <Another Peer Address>
         call <In Route-Map for this Peer>

   This is exactly the process that has been followed to generate the
route-map RSCLIENT-A-IMPORT. The route-maps that are called inside it
(A-IMPORT-FROM-B and A-IMPORT-FROM-C) are exactly the same than the In
route-maps from the original configuration of RA (PEER-B-IN and
PEER-C-IN), only the name is different.

   The same could have been done to create the Export policy for RA
(route-map RSCLIENT-A-EXPORT), but in this case the original Out
route-maps where so simple that we decided not to use the CALL WORD
commands, and we integrated all in a single route-map
(RSCLIENT-A-EXPORT).

   The Import and Export policies for RB and RC are not shown, but the
process would be identical.

\1f
File: quagga.info,  Node: Further considerations about Import and Export route-maps,  Prev: Configuration of the Route Server itself,  Up: Example of Route Server Configuration

12.3.4 Further considerations about Import and Export route-maps
----------------------------------------------------------------

The current version of the route server patch only allows to specify a
route-map for import and export policies, while in a standard BGP
speaker apart from route-maps there are other tools for performing input
and output filtering (access-lists, community-lists, ...).  But this
does not represent any limitation, as all kinds of filters can be
included in import/export route-maps.  For example suppose that in the
non-route-server scenario peer RA had the following filters configured
for input from peer B:

         neighbor 2001:0DB8::B prefix-list LIST-1 in
         neighbor 2001:0DB8::B filter-list LIST-2 in
         neighbor 2001:0DB8::B route-map PEER-B-IN in
         ...
         ...
     route-map PEER-B-IN permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set local-preference 100
     route-map PEER-B-IN permit 20
       match ipv6 address prefix-list PEER-B-PREFIXES
       set community 65001:11111

   It is posible to write a single route-map which is equivalent to the
three filters (the community-list, the prefix-list and the route-map).
That route-map can then be used inside the Import policy in the route
server.  Lets see how to do it:

         neighbor 2001:0DB8::A route-map RSCLIENT-A-IMPORT import
         ...
     !
     ...
     route-map RSCLIENT-A-IMPORT permit 10
       match peer 2001:0DB8::B
       call A-IMPORT-FROM-B
     ...
     ...
     !
     route-map A-IMPORT-FROM-B permit 1
       match ipv6 address prefix-list LIST-1
       match as-path LIST-2
       on-match goto 10
     route-map A-IMPORT-FROM-B deny 2
     route-map A-IMPORT-FROM-B permit 10
       match ipv6 address prefix-list COMMON-PREFIXES
       set local-preference 100
     route-map A-IMPORT-FROM-B permit 20
       match ipv6 address prefix-list PEER-B-PREFIXES
       set community 65001:11111
     !
     ...
     ...

   The route-map A-IMPORT-FROM-B is equivalent to the three filters
(LIST-1, LIST-2 and PEER-B-IN). The first entry of route-map
A-IMPORT-FROM-B (sequence number 1) matches if and only if both the
prefix-list LIST-1 and the filter-list LIST-2 match.  If that happens,
due to the "on-match goto 10" statement the next route-map entry to be
processed will be number 10, and as of that point route-map
A-IMPORT-FROM-B is identical to PEER-B-IN. If the first entry does not
match, 'on-match goto 10" will be ignored and the next processed entry
will be number 2, which will deny the route.

   Thus, the result is the same that with the three original filters,
i.e., if either LIST-1 or LIST-2 rejects the route, it does not reach
the route-map PEER-B-IN. In case both LIST-1 and LIST-2 accept the
route, it passes to PEER-B-IN, which can reject, accept or modify the
route.

\1f
File: quagga.info,  Node: VTY shell,  Next: Filtering,  Prev: Configuring Quagga as a Route Server,  Up: Top

13 VTY shell
************

'vtysh' is integrated shell of Quagga software.

   To use vtysh please specify --enable-vtysh to configure script.  To
use PAM for authentication use --with-libpam option to configure script.

   vtysh only searches /etc/quagga path for vtysh.conf which is the
vtysh configuration file.  Vtysh does not search current directory for
configuration file because the file includes user authentication
settings.

   Currently, vtysh.conf has only two commands.

* Menu:

* VTY shell username::
* VTY shell integrated configuration::

\1f
File: quagga.info,  Node: VTY shell username,  Next: VTY shell integrated configuration,  Up: VTY shell

13.1 VTY shell username
=======================

 -- Command: username USERNAME nopassword

     With this set, user foo does not need password authentication for
     user vtysh.  With PAM vtysh uses PAM authentication mechanism.

     If vtysh is compiled without PAM authentication, every user can use
     vtysh without authentication.  vtysh requires read/write permission
     to the various daemons vty sockets, this can be accomplished
     through use of unix groups and the -enable-vty-group configure
     option.

\1f
File: quagga.info,  Node: VTY shell integrated configuration,  Prev: VTY shell username,  Up: VTY shell

13.2 VTY shell integrated configuration
=======================================

 -- Command: service integrated-vtysh-config
     Write out integrated Quagga.conf file when 'write file' is issued.

     This command controls the behaviour of vtysh when it is told to
     write out the configuration.  Per default, vtysh will instruct each
     daemon to write out their own config files when 'write file' is
     issued.  However, if 'service integrated-vtysh-config' is set, when
     'write file' is issued, vtysh will instruct the daemons will write
     out a Quagga.conf with all daemons' commands integrated into it.

     Vtysh per default behaves as if 'write-conf daemon' is set.  Note
     that both may be set at same time if one wishes to have both
     Quagga.conf and daemon specific files written out.  Further, note
     that the daemons are hard-coded to first look for the integrated
     Quagga.conf file before looking for their own file.

     We recommend you do not mix the use of the two types of files.
     Further, it is better not to use the integrated Quagga.conf file,
     as any syntax error in it can lead to /all/ of your daemons being
     unable to start up.  Per daemon files are more robust as impact of
     errors in configuration are limited to the daemon in whose file the
     error is made.

\1f
File: quagga.info,  Node: Filtering,  Next: Route Map,  Prev: VTY shell,  Up: Top

14 Filtering
************

Quagga provides many very flexible filtering features.  Filtering is
used for both input and output of the routing information.  Once
filtering is defined, it can be applied in any direction.

* Menu:

* IP Access List::              
* IP Prefix List::              

\1f
File: quagga.info,  Node: IP Access List,  Next: IP Prefix List,  Up: Filtering

14.1 IP Access List
===================

 -- Command: access-list NAME permit IPV4-NETWORK
 -- Command: access-list NAME deny IPV4-NETWORK

   Basic filtering is done by 'access-list' as shown in the following
example.

     access-list filter deny 10.0.0.0/9
     access-list filter permit 10.0.0.0/8

\1f
File: quagga.info,  Node: IP Prefix List,  Prev: IP Access List,  Up: Filtering

14.2 IP Prefix List
===================

'ip prefix-list' provides the most powerful prefix based filtering
mechanism.  In addition to 'access-list' functionality, 'ip prefix-list'
has prefix length range specification and sequential number
specification.  You can add or delete prefix based filters to arbitrary
points of prefix-list using sequential number specification.

   If no ip prefix-list is specified, it acts as permit.  If 'ip
prefix-list' is defined, and no match is found, default deny is applied.

 -- Command: ip prefix-list NAME (permit|deny) PREFIX [le LEN] [ge LEN]
 -- Command: ip prefix-list NAME seq NUMBER (permit|deny) PREFIX [le
          LEN] [ge LEN]

     You can create 'ip prefix-list' using above commands.

     seq
          seq NUMBER can be set either automatically or manually.  In
          the case that sequential numbers are set manually, the user
          may pick any number less than 4294967295.  In the case that
          sequential number are set automatically, the sequential number
          will increase by a unit of five (5) per list.  If a list with
          no specified sequential number is created after a list with a
          specified sequential number, the list will automatically pick
          the next multiple of five (5) as the list number.  For
          example, if a list with number 2 already exists and a new list
          with no specified number is created, the next list will be
          numbered 5.  If lists 2 and 7 already exist and a new list
          with no specified number is created, the new list will be
          numbered 10.

     le
          'le' command specifies prefix length.  The prefix list will be
          applied if the prefix length is less than or equal to the le
          prefix length.

     ge
          'ge' command specifies prefix length.  The prefix list will be
          applied if the prefix length is greater than or equal to the
          ge prefix length.

   Less than or equal to prefix numbers and greater than or equal to
prefix numbers can be used together.  The order of the le and ge
commands does not matter.

   If a prefix list with a different sequential number but with the
exact same rules as a previous list is created, an error will result.
However, in the case that the sequential number and the rules are
exactly similar, no error will result.

   If a list with the same sequential number as a previous list is
created, the new list will overwrite the old list.

   Matching of IP Prefix is performed from the smaller sequential number
to the larger.  The matching will stop once any rule has been applied.

   In the case of no le or ge command, the prefix length must match
exactly the length specified in the prefix list.

 -- Command: no ip prefix-list NAME

* Menu:

* ip prefix-list description::  
* ip prefix-list sequential number control::  
* Showing ip prefix-list::      
* Clear counter of ip prefix-list::  

\1f
File: quagga.info,  Node: ip prefix-list description,  Next: ip prefix-list sequential number control,  Up: IP Prefix List

14.2.1 ip prefix-list description
---------------------------------

 -- Command: ip prefix-list NAME description DESC
     Descriptions may be added to prefix lists.  This command adds a
     description to the prefix list.

 -- Command: no ip prefix-list NAME description [DESC]
     Deletes the description from a prefix list.  It is possible to use
     the command without the full description.

\1f
File: quagga.info,  Node: ip prefix-list sequential number control,  Next: Showing ip prefix-list,  Prev: ip prefix-list description,  Up: IP Prefix List

14.2.2 ip prefix-list sequential number control
-----------------------------------------------

 -- Command: ip prefix-list sequence-number
     With this command, the IP prefix list sequential number is
     displayed.  This is the default behavior.

 -- Command: no ip prefix-list sequence-number
     With this command, the IP prefix list sequential number is not
     displayed.

\1f
File: quagga.info,  Node: Showing ip prefix-list,  Next: Clear counter of ip prefix-list,  Prev: ip prefix-list sequential number control,  Up: IP Prefix List

14.2.3 Showing ip prefix-list
-----------------------------

 -- Command: show ip prefix-list
     Display all IP prefix lists.

 -- Command: show ip prefix-list NAME
     Show IP prefix list can be used with a prefix list name.

 -- Command: show ip prefix-list NAME seq NUM
     Show IP prefix list can be used with a prefix list name and
     sequential number.

 -- Command: show ip prefix-list NAME A.B.C.D/M
     If the command longer is used, all prefix lists with prefix lengths
     equal to or longer than the specified length will be displayed.  If
     the command first match is used, the first prefix length match will
     be displayed.

 -- Command: show ip prefix-list NAME A.B.C.D/M longer

 -- Command: show ip prefix-list NAME A.B.C.D/M first-match

 -- Command: show ip prefix-list summary
 -- Command: show ip prefix-list summary NAME

 -- Command: show ip prefix-list detail
 -- Command: show ip prefix-list detail NAME

\1f
File: quagga.info,  Node: Clear counter of ip prefix-list,  Prev: Showing ip prefix-list,  Up: IP Prefix List

14.2.4 Clear counter of ip prefix-list
--------------------------------------

 -- Command: clear ip prefix-list
     Clears the counters of all IP prefix lists.  Clear IP Prefix List
     can be used with a specified name and prefix.

 -- Command: clear ip prefix-list NAME

 -- Command: clear ip prefix-list NAME A.B.C.D/M

\1f
File: quagga.info,  Node: Route Map,  Next: IPv6 Support,  Prev: Filtering,  Up: Top

15 Route Map
************

Route maps provide a means to both filter and/or apply actions to route,
hence allowing policy to be applied to routes.

* Menu:

* Route Map Command::           
* Route Map Match Command::     
* Route Map Set Command::
* Route Map Call Command::
* Route Map Exit Action Command::
* Route Map Examples::

   Route-maps are an ordered list of route-map entries.  Each entry may
specify up to four distincts sets of clauses:

'Matching Policy'

     This specifies the policy implied if the 'Matching Conditions' are
     met or not met, and which actions of the route-map are to be taken,
     if any.  The two possibilities are:

        - 'permit': If the entry matches, then carry out the 'Set
          Actions'.  Then finish processing the route-map, permitting
          the route, unless an 'Exit Action' indicates otherwise.

        - 'deny': If the entry matches, then finish processing the
          route-map and deny the route (return 'deny').

     The 'Matching Policy' is specified as part of the command which
     defines the ordered entry in the route-map.  See below.

'Matching Conditions'

     A route-map entry may, optionally, specify one or more conditions
     which must be matched if the entry is to be considered further, as
     governed by the Match Policy.  If a route-map entry does not
     explicitely specify any matching conditions, then it always
     matches.

'Set Actions'

     A route-map entry may, optionally, specify one or more 'Set
     Actions' to set or modify attributes of the route.

'Call Action'

     Call to another route-map, after any 'Set Actions' have been
     carried out.  If the route-map called returns 'deny' then
     processing of the route-map finishes and the route is denied,
     regardless of the 'Matching Policy' or the 'Exit Policy'.  If the
     called route-map returns 'permit', then 'Matching Policy' and 'Exit
     Policy' govern further behaviour, as normal.

'Exit Policy'

     An entry may, optionally, specify an alternative 'Exit Policy' to
     take if the entry matched, rather than the normal policy of exiting
     the route-map and permitting the route.  The two possibilities are:

        - 'next': Continue on with processing of the route-map entries.

        - 'goto N': Jump ahead to the first route-map entry whose order
          in the route-map is >= N. Jumping to a previous entry is not
          permitted.

   The default action of a route-map, if no entries match, is to deny.
I.e.  a route-map essentially has as its last entry an empty 'deny'
entry, which matches all routes.  To change this behaviour, one must
specify an empty 'permit' entry as the last entry in the route-map.

   To summarise the above:

         Match    No Match
-----------------------------
_Permit_ action   cont
_Deny_   deny     cont

'action'
        - Apply _set_ statements

        - If _call_ is present, call given route-map.  If that returns a
          'deny', finish processing and return 'deny'.

        - If 'Exit Policy' is _next_, goto next route-map entry

        - If 'Exit Policy' is _goto_, goto first entry whose order in
          the list is >= the given order.

        - Finish processing the route-map and permit the route.

'deny'
        - The route is denied by the route-map (return 'deny').

'cont'
        - goto next route-map entry

\1f
File: quagga.info,  Node: Route Map Command,  Next: Route Map Match Command,  Up: Route Map

15.1 Route Map Command
======================

 -- Command: route-map ROUTE-MAP-NAME (permit|deny) ORDER

     Configure the ORDER'th entry in ROUTE-MAP-NAME with 'Match Policy'
     of either _permit_ or _deny_.

\1f
File: quagga.info,  Node: Route Map Match Command,  Next: Route Map Set Command,  Prev: Route Map Command,  Up: Route Map

15.2 Route Map Match Command
============================

 -- Route-map Command: match ip address ACCESS_LIST
     Matches the specified ACCESS_LIST

 -- Route-map Command: match ip next-hop IPV4_ADDR
     Matches the specified IPV4_ADDR.

 -- Route-map Command: match as-path AS_PATH
     Matches the specified AS_PATH.

 -- Route-map Command: match metric METRIC
     Matches the specified METRIC.

 -- Route-map Command: match local-preference METRIC
     Matches the specified LOCAL-PREFERENCE.

 -- Route-map Command: match community COMMUNITY_LIST
     Matches the specified COMMUNITY_LIST

\1f
File: quagga.info,  Node: Route Map Set Command,  Next: Route Map Call Command,  Prev: Route Map Match Command,  Up: Route Map

15.3 Route Map Set Command
==========================

 -- Route-map Command: set ip next-hop IPV4_ADDRESS
     Set the BGP nexthop address.

 -- Route-map Command: set local-preference LOCAL_PREF
     Set the BGP local preference.

 -- Route-map Command: set weight WEIGHT
     Set the route's weight.

 -- Route-map Command: set metric METRIC
     Set the BGP attribute MED.

 -- Route-map Command: set as-path prepend AS_PATH
     Set the BGP AS path to prepend.

 -- Route-map Command: set community COMMUNITY
     Set the BGP community attribute.

 -- Route-map Command: set ipv6 next-hop global IPV6_ADDRESS
     Set the BGP-4+ global IPv6 nexthop address.

 -- Route-map Command: set ipv6 next-hop local IPV6_ADDRESS
     Set the BGP-4+ link local IPv6 nexthop address.

\1f
File: quagga.info,  Node: Route Map Call Command,  Next: Route Map Exit Action Command,  Prev: Route Map Set Command,  Up: Route Map

15.4 Route Map Call Command
===========================

 -- Route-map Command: call NAME
     Call route-map NAME.  If it returns deny, deny the route and finish
     processing the route-map.

\1f
File: quagga.info,  Node: Route Map Exit Action Command,  Next: Route Map Examples,  Prev: Route Map Call Command,  Up: Route Map

15.5 Route Map Exit Action Command
==================================

 -- Route-map Command: on-match next
 -- Route-map Command: continue
     Proceed on to the next entry in the route-map.

 -- Route-map Command: on-match goto N
 -- Route-map Command: continue N
     Proceed processing the route-map at the first entry whose order is
     >= N

\1f
File: quagga.info,  Node: Route Map Examples,  Prev: Route Map Exit Action Command,  Up: Route Map

15.6 Route Map Examples
=======================

A simple example of a route-map:

     route-map test permit 10
      match ip address 10
      set local-preference 200

   This means that if a route matches ip access-list number 10 it's
local-preference value is set to 200.

   See *note BGP Configuration Examples:: for examples of more
sophisticated useage of route-maps, including of the 'call' action.

\1f
File: quagga.info,  Node: IPv6 Support,  Next: Kernel Interface,  Prev: Route Map,  Up: Top

16 IPv6 Support
***************

Quagga fully supports IPv6 routing.  As described so far, Quagga
supports RIPng, OSPFv3, and BGP-4+.  You can give IPv6 addresses to an
interface and configure static IPv6 routing information.  Quagga IPv6
also provides automatic address configuration via a feature called
'address auto configuration'.  To do it, the router must send router
advertisement messages to the all nodes that exist on the network.

* Menu:

* Router Advertisement::        

\1f
File: quagga.info,  Node: Router Advertisement,  Up: IPv6 Support

16.1 Router Advertisement
=========================

 -- Interface Command: no ipv6 nd suppress-ra
     Send router advertisment messages.

 -- Interface Command: ipv6 nd suppress-ra
     Don't send router advertisment messages.

 -- Interface Command: ipv6 nd prefix IPV6PREFIX [VALID-LIFETIME]
          [PREFERRED-LIFETIME] [off-link] [no-autoconfig]
          [router-address]
     Configuring the IPv6 prefix to include in router advertisements.
     Several prefix specific optional parameters and flags may follow:
        * VALID-LIFETIME - the length of time in seconds during what the
          prefix is valid for the purpose of on-link determination.
          Value INFINITE represents infinity (i.e.  a value of all one
          bits ('0xffffffff')).

          Range: '<0-4294967295>' Default: '2592000'

        * PREFERRED-LIFETIME - the length of time in seconds during what
          addresses generated from the prefix remain preferred.  Value
          INFINITE represents infinity.

          Range: '<0-4294967295>' Default: '604800'

        * OFF-LINK - indicates that advertisement makes no statement
          about on-link or off-link properties of the prefix.

          Default: not set, i.e.  this prefix can be used for on-link
          determination.

        * NO-AUTOCONFIG - indicates to hosts on the local link that the
          specified prefix cannot be used for IPv6 autoconfiguration.

          Default: not set, i.e.  prefix can be used for
          autoconfiguration.

        * ROUTER-ADDRESS - indicates to hosts on the local link that the
          specified prefix contains a complete IP address by setting R
          flag.

          Default: not set, i.e.  hosts do not assume a complete IP
          address is placed.

 -- Interface Command: ipv6 nd ra-interval <1-1800>
 -- Interface Command: no ipv6 nd ra-interval [<1-1800>]
     The maximum time allowed between sending unsolicited multicast
     router advertisements from the interface, in seconds.

     Default: '600'

 -- Interface Command: ipv6 nd ra-interval msec <70-1800000>
 -- Interface Command: no ipv6 nd ra-interval [msec <70-1800000>]
     The maximum time allowed between sending unsolicited multicast
     router advertisements from the interface, in milliseconds.

     Default: '600000'

 -- Interface Command: ipv6 nd ra-lifetime <0-9000>
 -- Interface Command: no ipv6 nd ra-lifetime [<0-9000>]
     The value to be placed in the Router Lifetime field of router
     advertisements sent from the interface, in seconds.  Indicates the
     usefulness of the router as a default router on this interface.
     Setting the value to zero indicates that the router should not be
     considered a default router on this interface.  Must be either zero
     or between value specified with IPV6 ND RA-INTERVAL (or default)
     and 9000 seconds.

     Default: '1800'

 -- Interface Command: ipv6 nd reachable-time <1-3600000>
 -- Interface Command: no ipv6 nd reachable-time [<1-3600000>]
     The value to be placed in the Reachable Time field in the Router
     Advertisement messages sent by the router, in milliseconds.  The
     configured time enables the router to detect unavailable neighbors.
     The value zero means unspecified (by this router).

     Default: '0'

 -- Interface Command: ipv6 nd managed-config-flag
 -- Interface Command: no ipv6 nd managed-config-flag
     Set/unset flag in IPv6 router advertisements which indicates to
     hosts that they should use managed (stateful) protocol for
     addresses autoconfiguration in addition to any addresses
     autoconfigured using stateless address autoconfiguration.

     Default: not set

 -- Interface Command: ipv6 nd other-config-flag
 -- Interface Command: no ipv6 nd other-config-flag
     Set/unset flag in IPv6 router advertisements which indicates to
     hosts that they should use administered (stateful) protocol to
     obtain autoconfiguration information other than addresses.

     Default: not set

 -- Interface Command: ipv6 nd home-agent-config-flag
 -- Interface Command: no ipv6 nd home-agent-config-flag
     Set/unset flag in IPv6 router advertisements which indicates to
     hosts that the router acts as a Home Agent and includes a Home
     Agent Option.

     Default: not set

 -- Interface Command: ipv6 nd home-agent-preference <0-65535>
 -- Interface Command: no ipv6 nd home-agent-preference [<0-65535>]
     The value to be placed in Home Agent Option, when Home Agent config
     flag is set, which indicates to hosts Home Agent preference.  The
     default value of 0 stands for the lowest preference possible.

     Default: 0

 -- Interface Command: ipv6 nd home-agent-lifetime <0-65520>
 -- Interface Command: no ipv6 nd home-agent-lifetime [<0-65520>]
     The value to be placed in Home Agent Option, when Home Agent config
     flag is set, which indicates to hosts Home Agent Lifetime.  The
     default value of 0 means to place the current Router Lifetime
     value.

     Default: 0

 -- Interface Command: ipv6 nd adv-interval-option
 -- Interface Command: no ipv6 nd adv-interval-option
     Include an Advertisement Interval option which indicates to hosts
     the maximum time, in milliseconds, between successive unsolicited
     Router Advertisements.

     Default: not set

 -- Interface Command: ipv6 nd router-preference (high|medium|low)
 -- Interface Command: no ipv6 nd router-preference [(high|medium|low)]
     Set default router preference in IPv6 router advertisements per
     RFC4191.

     Default: medium

 -- Interface Command: ipv6 nd mtu <1-65535>
 -- Interface Command: no ipv6 nd mtu [<1-65535>]
     Include an MTU (type 5) option in each RA packet to assist the
     attached hosts in proper interface configuration.  The announced
     value is not verified to be consistent with router interface MTU.

     Default: don't advertise any MTU option

     interface eth0
      no ipv6 nd suppress-ra
      ipv6 nd prefix 2001:0DB8:5009::/64

   For more information see 'RFC2462 (IPv6 Stateless Address
Autoconfiguration)' , 'RFC4861 (Neighbor Discovery for IP Version 6
(IPv6))' , 'RFC6275 (Mobility Support in IPv6)' and 'RFC4191 (Default
Router Preferences and More-Specific Routes)'.

\1f
File: quagga.info,  Node: Kernel Interface,  Next: SNMP Support,  Prev: IPv6 Support,  Up: Top

17 Kernel Interface
*******************

There are several different methods for reading kernel routing table
information, updating kernel routing tables, and for looking up
interfaces.

'ioctl'
     The 'ioctl' method is a very traditional way for reading or writing
     kernel information.  'ioctl' can be used for looking up interfaces
     and for modifying interface addresses, flags, mtu settings and
     other types of information.  Also, 'ioctl' can insert and delete
     kernel routing table entries.  It will soon be available on almost
     any platform which zebra supports, but it is a little bit ugly thus
     far, so if a better method is supported by the kernel, zebra will
     use that.

'sysctl'
     'sysctl' can lookup kernel information using MIB (Management
     Information Base) syntax.  Normally, it only provides a way of
     getting information from the kernel.  So one would usually want to
     change kernel information using another method such as 'ioctl'.

'proc filesystem'
     'proc filesystem' provides an easy way of getting kernel
     information.

'routing socket'

'netlink'
     On recent Linux kernels (2.0.x and 2.2.x), there is a kernel/user
     communication support called 'netlink'.  It makes asynchronous
     communication between kernel and Quagga possible, similar to a
     routing socket on BSD systems.

     Before you use this feature, be sure to select (in kernel
     configuration) the kernel/netlink support option 'Kernel/User
     network link driver' and 'Routing messages'.

     Today, the /dev/route special device file is obsolete.  Netlink
     communication is done by reading/writing over netlink socket.

     After the kernel configuration, please reconfigure and rebuild
     Quagga.  You can use netlink as a dynamic routing update channel
     between Quagga and the kernel.

\1f
File: quagga.info,  Node: SNMP Support,  Next: Zebra Protocol,  Prev: Kernel Interface,  Up: Top

18 SNMP Support
***************

SNMP (Simple Network Managing Protocol) is a widely implemented feature
for collecting network information from router and/or host.  Quagga
itself does not support SNMP agent (server daemon) functionality but is
able to connect to a SNMP agent using the SMUX protocol ('RFC1227') or
the AgentX protocol ('RFC2741') and make the routing protocol MIBs
available through it.

* Menu:

* Getting and installing an SNMP agent::
* AgentX configuration::
* SMUX configuration::
* MIB and command reference::
* Handling SNMP Traps::

\1f
File: quagga.info,  Node: Getting and installing an SNMP agent,  Next: AgentX configuration,  Up: SNMP Support

18.1 Getting and installing an SNMP agent
=========================================

There are several SNMP agent which support SMUX or AgentX. We recommend
to use the latest version of 'net-snmp' which was formerly known as
'ucd-snmp'.  It is free and open software and available at
<http://www.net-snmp.org/> and as binary package for most Linux
distributions.  'net-snmp' has to be compiled with
'--with-mib-modules=agentx' to be able to accept connections from Quagga
using AgentX protocol or with '--with-mib-modules=smux' to use SMUX
protocol.

   Nowadays, SMUX is a legacy protocol.  The AgentX protocol should be
preferred for any new deployment.  Both protocols have the same
coverage.

\1f
File: quagga.info,  Node: AgentX configuration,  Next: SMUX configuration,  Prev: Getting and installing an SNMP agent,  Up: SNMP Support

18.2 AgentX configuration
=========================

To enable AgentX protocol support, Quagga must have been build with the
'--enable-snmp' or '--enable-snmp=agentx' option.  Both the master SNMP
agent (snmpd) and each of the Quagga daemons must be configured.  In
'/etc/snmp/snmpd.conf', 'master agentx' directive should be added.  In
each of the Quagga daemons, 'agentx' command will enable AgentX support.

     /etc/snmp/snmpd.conf:
        #
        # example access restrictions setup
        #
        com2sec readonly default public
        group MyROGroup v1 readonly
        view all included .1 80
        access MyROGroup "" any noauth exact all none none
        #
        # enable master agent for AgentX subagents
        #
        master agentx

     /etc/quagga/ospfd.conf:
        ! ... the rest of ospfd.conf has been omitted for clarity ...
        !
        agentx
        !

   Upon successful connection, you should get something like this in the
log of each Quagga daemons:

     2012/05/25 11:39:08 ZEBRA: snmp[info]: NET-SNMP version 5.4.3 AgentX subagent connected

   Then, you can use the following command to check everything works as
expected:

     # snmpwalk -c public -v1 localhost .1.3.6.1.2.1.14.1.1
     OSPF-MIB::ospfRouterId.0 = IpAddress: 192.168.42.109
     [...]

   The AgentX protocol can be transported over a Unix socket or using
TCP or UDP. It usually defaults to a Unix socket and depends on how
NetSNMP was built.  If need to configure Quagga to use another
transport, you can configure it through '/etc/snmp/quagga.conf':

     /etc/snmp/quagga.conf:
        [snmpd]
        # Use a remote master agent
        agentXSocket tcp:192.168.15.12:705

\1f
File: quagga.info,  Node: SMUX configuration,  Next: MIB and command reference,  Prev: AgentX configuration,  Up: SNMP Support

18.3 SMUX configuration
=======================

To enable SMUX protocol support, Quagga must have been build with the
'--enable-snmp=smux' option.

   A separate connection has then to be established between the SNMP
agent (snmpd) and each of the Quagga daemons.  This connections each use
different OID numbers and passwords.  Be aware that this OID number is
not the one that is used in queries by clients, it is solely used for
the intercommunication of the daemons.

   In the following example the ospfd daemon will be connected to the
snmpd daemon using the password "quagga_ospfd".  For testing it is
recommending to take exactly the below snmpd.conf as wrong access
restrictions can be hard to debug.

     /etc/snmp/snmpd.conf:
        #
        # example access restrictions setup
        #
        com2sec readonly default public
        group MyROGroup v1 readonly
        view all included .1 80
        access MyROGroup "" any noauth exact all none none
        #
        # the following line is relevant for Quagga
        #
        smuxpeer .1.3.6.1.4.1.3317.1.2.5 quagga_ospfd

     /etc/quagga/ospf:
        ! ... the rest of ospfd.conf has been omitted for clarity ...
        !
        smux peer .1.3.6.1.4.1.3317.1.2.5 quagga_ospfd
        !

   After restarting snmpd and quagga, a successful connection can be
verified in the syslog and by querying the SNMP daemon:

     snmpd[12300]: [smux_accept] accepted fd 12 from 127.0.0.1:36255
     snmpd[12300]: accepted smux peer: \
        oid GNOME-PRODUCT-ZEBRA-MIB::ospfd, quagga-0.96.5

     # snmpwalk -c public -v1 localhost .1.3.6.1.2.1.14.1.1
     OSPF-MIB::ospfRouterId.0 = IpAddress: 192.168.42.109

   Be warned that the current version (5.1.1) of the Net-SNMP daemon
writes a line for every SNMP connect to the syslog which can lead to
enormous log file sizes.  If that is a problem you should consider to
patch snmpd and comment out the troublesome 'snmp_log()' line in the
function 'netsnmp_agent_check_packet()' in 'agent/snmp_agent.c'.