+++ /dev/null
-# $QuaggaId: $Format:%an, %ai, %h$ $
-
-C1 IGMPv3 backward compatibility with IGMPv1 and IGMPv2 is not
- implemented. See RFC 3376, 7.3. Multicast Router Behavior. That's
- because only Source-Specific Multicast is currently targeted.
-
-C2 IGMPv3 support for forwarding any-source groups is not
- implemented. Traffic for groups in mode EXCLUDE {empty} won't be
- forwarded. See RFC 3376, 6.3. Source-Specific Forwarding
- Rules. That's because only Source-Specific Multicast is currently
- targeted.
-
-C3 Load Splitting of IP Multicast Traffic over ECMP is not supported.
- See also: RFC 2991
- Multipath Issues in Unicast and Multicast Next-Hop Selection
- http://www.rfc-editor.org/rfc/rfc2991.txt
-
-C4 IPSec AH authentication is not supported (RFC 4601:
- 6.3. Authentication Using IPsec).
-
-C5 PIM support is limited to SSM mode as defined in section 4.8.2
- (PIM-SSM-Only Routers) of RFC4601. That's because only
- Source-Specific Multicast is currently targeted.
-
-C6 PIM implementation currently does not support IPv6. PIM-SSM
- requires IGMPv3 for IPv4 and MLDv2 for IPv6. MLDv2 is currently
- missing. See also CAVEAT C9.
-
-C7 FIXED (S,G) Assert state machine (RFC 4601, section 4.6.1) is not
- implemented. See also TODO T6. See also CAVEAT C10.
-
-C8 It is not possible to disable join suppression in order to
- explicitly track the join membership of individual downstream
- routers.
- - IGMPv3 Explicit Membership Tracking is not supported.
- When explicit tracking is enabled on a router, the router can
- individually track the Internet Group Management Protocol (IGMP)
- membership state of all reporting hosts. This feature allows the
- router to achieve minimal leave latencies when hosts leave a
- multicast group or channel. Example:
- conf t
- interface eth0
- ip igmp explicit-tracking
-
-C9 Only IPv4 Address Family (number=1) is supported in the PIM Address
- Family field.
- See also RFC 4601: 5.1. PIM Address Family
- See also CAVEAT C6.
- See also http://www.iana.org/assignments/address-family-numbers
-
-C10 FIXED Assert metric depends on metric_preference and
- route_metric. Those parameters should be fetched from RIB
- (zebra). See also pim_rpf.c, pim_rpf_update().
-
-C11 SSM Mapping is not supported
-
- SSM Mapping Overview:
-
- SSM mapping introduces a means for the last hop router to discover
- sources sending to groups. When SSM mapping is configured, if a
- router receives an IGMPv1 or IGMPv2 membership report for a
- particular group G, the router translates this report into one or
- more (S, G) channel memberships for the well-known sources
- associated with this group.
-
- When the router receives an IGMPv1 or IGMPv2 membership report for
- a group G, the router uses SSM mapping to determine one or more
- source IP addresses for the group G. SSM mapping then translates
- the membership report as an IGMPv3 report INCLUDE (G, [S1, G],
- [S2, G]...[Sn, G] and continues as if it had received an IGMPv3
- report. The router then sends out PIM joins toward (S1, G) to (Sn,
- G) and continues to be joined to these groups as long as it
- continues to receive the IGMPv1 or IGMPv2 membership reports and
- as long as the SSM mapping for the group remains the same. SSM
- mapping, thus, enables you to leverage SSM for video delivery to
- legacy STBs that do not support IGMPv3 or for applications that do
- not take advantage of the IGMPv3 host stack.
-
- SSM mapping enables the last hop router to determine the source
- addresses either by a statically configured table on the router or
- by consulting a DNS server. When the statically configured table
- is changed, or when the DNS mapping changes, the router will leave
- the current sources associated with the joined groups.
-
-C12 FIXED MRIB for incongruent unicast/multicast topologies is not
- supported. RPF mechanism currently just looks up the information
- in the unicast routing table.
-
- See also:
- RFC5110: 2.2.3. Issue: Overlapping Unicast/Multicast Topology
-
- Sometimes, multicast RPF mechanisms first look up the multicast
- routing table, or M-RIB ("topology database") with a longest
- prefix match algorithm, and if they find any entry (including a
- default route), that is used; if no match is found, the unicast
- routing table is used instead.
-
-C13 Can't detect change of primary address before the actual change.
- Possible approach is to craft old interface address into ip source
- address by using raw ip socket.
-
- See also:
-
- RFC 4601: 4.3.1. Sending Hello Messages
-
- Before an interface goes down or changes primary IP address, a
- Hello message with a zero HoldTime should be sent immediately
- (with the old IP address if the IP address changed).
-
- See also pim_sock_delete().
-
-C14 FIXED Detection of interface primary address changes may fail when
- there are multiple addresses.
- See also TODO T32.
-
-C15 Changes in interface secondary address list are not immediately
- detected.
- See also detect_secondary_address_change
- See also TODO T31.
-
-C16 AMT Draft (mboned-auto-multicast) is not supported.
- AMT = Automatic IP Multicast Without Explicit Tunnels
-
- See also:
-
- Draft
- http://tools.ietf.org/html/draft-ietf-mboned-auto-multicast
- http://tools.ietf.org/html/draft-ietf-mboned-auto-multicast-09
-
- AMT gateway implementation for Linux
- http://cs.utdallas.edu/amt/
-
- AMT for Streaming (IPTV) on Global IP Multicast by Greg Shepherd (Cisco)
- http://nznog.miniconf.org/nznog-2008-sysadmin-miniconf-greg-shepherd-iptv.pdf
-
-C17 SNMP / RFC 5060 (PIM MIB) is not supported.
-
-C18 MFC never recovers from removal of static route to source
-
- # route add -host 1.2.3.4 gw 192.168.56.10
- Before removal:
- quagga-pimd-router# sh ip mroute
- Source Group Proto Input iVifI Output oVifI TTL Uptime
- 1.2.3.4 232.1.2.3 I eth1 3 eth0 2 1 00:00:36
-
- # route del -host 1.2.3.4 gw 192.168.56.10
- After removal: sh ip mroute --> empty output
-
- # route add -host 1.2.3.4 gw 192.168.56.10
- After the route is restored: sh ip mroute --> never recovers (empty output)
-
- At this point, "no ip pim ssm" on the upstream interface (eth0) crashes pimd:
-
- 2014/02/14 16:30:14 PIM: ifmembership_set: (S,G)=(1.2.3.4,232.1.2.3) membership now is NOINFO on interface eth0
- 2014/02/14 16:30:14 PIM: pim_ifchannel_update_assert_tracking_desired: AssertTrackingDesired(1.2.3.4,232.1.2.3,eth0) changed from 1 to 0
- 2014/02/14 16:30:14 PIM: pim_zebra.c del_oif: nonexistent protocol mask 2 removed OIF eth0 (vif_index=2, min_ttl=0) from channel (S,G)=(1.2.3.4,232.1.2.3)
- 2014/02/14 16:30:14 PIM: pim_ifchannel_update_could_assert: CouldAssert(1.2.3.4,232.1.2.3,eth0) changed from 1 to 0
- 2014/02/14 16:30:14 PIM: pim_ifchannel_update_my_assert_metric: my_assert_metric(1.2.3.4,232.1.2.3,eth0) changed from 0,0,0,10.0.2.15 to 1,4294967295,4294967295,0.0.0.0
- 2014/02/14 16:30:14 PIM: pim_zebra.c del_oif: nonexistent protocol mask 1 removed OIF eth0 (vif_index=2, min_ttl=0) from channel (S,G)=(1.2.3.4,232.1.2.3)
- 2014/02/14 16:30:14 PIM: Assertion `!IGMP_SOURCE_TEST_FORWARDING(source->source_flags)' failed in file pim_igmpv3.c, line 412, function igmp_source_delete
-
-C19 Provision to prevent group mode clash
-
- Beware group mode clash. A host/application issuing IGMPv2
- any-source joins for a group will disrupt SSM multicast for that
- group.
-
- For instance, support for source-specific static igmp WILL FAIL if
- there is host/application issuing IGMPv2 any-source joins for the
- same group.
-
- The reason is the IGMPv2 any-source join forces qpimd to switch
- the group mode to ASM (any-source multicast); however, qpimd is
- unable to program ASM groups into the kernel; multicast won't
- flow. There could be some provision to prevent such a behavior,
- but currently there is none.
-
--x-
projects / quagga-debian.git / blobdiff