embedaddon/quagga/pimd/TODO - view

File: [ELWIX - Embedded LightWeight unIX -] / embedaddon / quagga / pimd / TODO
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Wed Nov 2 10:09:11 2016 UTC (8 years, 1 month ago) by misho
Branches: quagga, MAIN
CVS tags: v1_0_20160315, HEAD

quagga 1.0.20160315

# $QuaggaId: $Format:%an, %ai, %h$ $ T1 DONE Implement debug command test pim receive join T2 DONE Implement debug command test pim receive prune T3 DONE Per-interface Downstream (S,G) state machine (RFC 4601 4.5.3. Receiving (S,G) Join/Prune Messages) T4 DONE Upstream (S,G) state machine (RFC 4601 4.5.7. Sending (S,G) Join/Prune Messages) T5 DONE Verify Data Packet Forwarding Rules RFC 4601 4.2. Data Packet Forwarding Rules RFC 4601 4.8.2. PIM-SSM-Only Routers Additionally, the Packet forwarding rules of Section 4.2 can be simplified in a PIM-SSM-only router: iif is the incoming interface of the packet. oiflist = NULL if (iif == RPF_interface(S) AND UpstreamJPState(S,G) == Joined) { oiflist = inherited_olist(S,G) } else if (iif is in inherited_olist(S,G)) { send Assert(S,G) on iif } oiflist = oiflist (-) iif forward packet on all interfaces in oiflist Macro: inherited_olist(S,G) = joins(S,G) (+) pim_include(S,G) (-) lost_assert(S,G) T6 DONE Implement (S,G) Assert state machine (RFC 4601, section 4.6.1). Changes in pim_ifchannel.ifassert_winner should trigger pim_upstream_update_join_desired(). Depends on TODO T27. Depends on TODO T33. See also CAVEAT C7. See also: RFC 4601 4.5.7. Sending (S,G) Join/Prune Messages Transitions from Joined State RPF'(S,G) changes due to an Assert http://www.hep.ucl.ac.uk/~ytl/multi-cast/pim-dm_01.html: The PIM Assert mechanism is used to shutoff duplicate flows onto the same multiaccess network. Routers detect this condiction when they receive an (S,G) packet via a multi-access interface that is in the (S,G) OIL. This causes the routers to send Assert Messages. Note that neighbors will not accept Join/Prune or Assert messages from a router unless they have first heard a Hello message from that router. Thus, if a router needs to send a Join/Prune or Assert message on an interface on which it has not yet sent a Hello message with the currently configured IP address, then it MUST immediately send the relevant Hello message without waiting for the Hello Timer to expire, followed by the Join/Prune or Assert message. T7 DONE Implement hello option: LAN Prune Delay T8 DONE Implement J/P_Override_Interval(I) Depends on TODO T7. See pim_ifchannel.c, pim_ifchannel_prune(), jp_override_interval. T9 DONE Detect change in IGMPv3 RPF interface/next-hop for S and update. channel_oil vif index accordingly ? Beware accidentaly adding looped MFC entries (IIF=OIF). T10 DONE React to (S,G) join directed to another upstream address. See also: RFC 4601: 4.5.7. Sending (S,G) Join/Prune Messages If a router wishes to propagate a Join(S,G) upstream, it must also watch for messages on its upstream interface from other routers on that subnet, and these may modify its behavior. If it sees a Join(S,G) to the correct upstream neighbor, it should suppress its own Join(S,G). If it sees a Prune(S,G), Prune(S,G,rpt), or Prune(*,G) to the correct upstream neighbor towards S, it should be prepared to override that prune by scheduling a Join(S,G) to be sent almost immediately. T11 DONE Review protocol modifications for SSM (RFC 4601 4.8.1. Protocol Modifications for SSM Destination Addresses) T12 DONE Review updates of RPF entries. FIXME pim_upstream.c send_join(): Currently only one upstream state is affected by detection of RPF change. RPF change should affect all upstream states sharing the RPF cache. T13 DONE Check that RFC macros using S,G,RPF_interface(S) are actually implemented with this strategy: rpf_ifch=find_ifch(up->rpf->interface). See pim_rpf.c pim_rpf_find_rpf_addr() for a correct example. $ grep -i macro pimd/*.c pimd/pim_iface.c: RFC 4601: 4.1.6. State Summarization Macros pimd/pim_ifchannel.c: RFC 4601: 4.6.5. Assert State Macros pimd/pim_ifchannel.c: RFC 4601: 4.1.6. State Summarization Macros pimd/pim_ifchannel.c: RFC 4601: 4.1.6. State Summarization Macros pimd/pim_ifchannel.c: RFC 4601: 4.6.5. Assert State Macros pimd/pim_ifchannel.c: Macro: pimd/pim_rpf.c: RFC 4601: 4.1.6. State Summarization Macros T14 DONE Send Assert(S,G) on iif as response to WRONGVIF kernel upcall. See pim_mroute.c mroute_msg(). T15 DONE Interface command to statically join (S,G). interface eth0 ip igmp join-group 239.1.1.1 source 1.1.1.1 T16 DONE RPF'(S,G) lookup is not working for S reachable with default route. See "RPF'(S,G) not found" in pim_rpf_update() from pim_rpf.c. Zebra daemon RIB is not reflecting changes in kernel routes accurately? T17 DONE Prevent CLI from creating bogus interfaces. Example: conf t interface xxx T18 Consider reliable pim solution (refresh reduction) A Reliable Transport Mechanism for PIM http://tools.ietf.org/wg/pim/draft-ietf-pim-port/ PORT=PIM-Over-Reliable-Transport T19 DONE Fix self as neighbor See mailing list post: http://lists.gnu.org/archive/html/qpimd-users/2009-04/msg00000.html T20 DONE Fix debug message: "pim_neighbor_update: internal error: trying to replace same prefix list" See mailing list post: http://lists.gnu.org/archive/html/qpimd-users/2009-04/msg00000.html T21 DONE Clean-up PIM/IGMP interface mismatch debugging See option PIM_CHECK_RECV_IFINDEX_SANITY in pimd/Makefile.am See mailing list post: http://lists.nongnu.org/archive/html/qpimd-users/2009-04/msg00003.html T22 DONE IGMP must be protected against adding looped MFC entries created by both source and receiver attached to the same interface. T23 DONE libzebra crash after zclient_lookup_nexthop. See mailing list post: http://lists.nongnu.org/archive/html/qpimd-users/2009-04/msg00008.html T24 DONE zserv may return recursive routes: - nexthop type is set to ZEBRA_NEXTHOP_IPV4 - ifindex is not reported - calls expecting ifindex (fib_lookup_if_vif_index) are disrupted See also this mailing list post: [PATCH 21/21] Link detect and recursive routes http://www.gossamer-threads.com/lists/quagga/dev/17564 T25 DONE Zclient nexthop lookup missing OSPF route to 1.1.1.1/32 See also: pim_zlookup.c zclient_lookup_nexthop misses OSPF 1.1.1.1/32 zebra/zebra_vty.c show_ip_route_addr_cmd hits OSPF 1.1.1.1/32 T26 DONE Zebra daemon is marking recursive static route as inactive. FIXED: zebra daemon was incorrectly marking recursive routes pointing to kernel routes as inactive: zebra/zebra_rib.c nexthop_active_ipv4: -- Original: else if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_INTERNAL)) -- Fixed: else if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_INTERNAL) || match->type == ZEBRA_ROUTE_KERNEL) Old problem description: This prevents rib_match_ipv4 from returning its nexthop: client: pim_zlookup.c zclient_read_nexthop server: zebra/zserv.c zsend_ipv4_nexthop_lookup_v2 -> rib_match_ipv4 Kernel route is injected into zebra in zebra_rib.c rib_add_ipv4 Examples: rt_netlink.c:726: rib_add_ipv4 (ZEBRA_ROUTE_KERNEL, flags, &p, gate, src, index, table, metric, 0); rt_netlink.c:864: rib_add_ipv4 (ZEBRA_ROUTE_KERNEL, 0, &p, gate, src, index, table, 0, 0); This patch didn't fix the issue: [PATCH 21/21] Link detect and recursive routes http://www.gossamer-threads.com/lists/quagga/dev/17564 See the example below for the route 2.2.2.2. bash# route add -host 1.1.1.1 gw 127.0.0.1 bash# route add -host 2.2.2.2 gw 1.1.1.1 bash# netstat -nvr Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 2.2.2.2 1.1.1.1 255.255.255.255 UGH 0 0 0 lo 1.1.1.1 127.0.0.1 255.255.255.255 UGH 0 0 0 lo 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0.0.0.0 192.168.0.2 0.0.0.0 UG 0 0 0 eth0 bash# zebra# sh ip route Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - ISIS, B - BGP, > - selected route, * - FIB route K>* 0.0.0.0/0 via 192.168.0.2, eth0 K>* 1.1.1.1/32 via 127.0.0.1, lo K * 2.2.2.2/32 via 1.1.1.1, lo inactive C>* 127.0.0.0/8 is directly connected, lo C>* 192.168.0.0/24 is directly connected, eth0 quagga-pimd-router# sh ip route 1.1.1.1 Address NextHop Interface Metric Preference 1.1.1.1 127.0.0.1 lo 0 0 quagga-pimd-router# quagga-pimd-router# sh ip route 2.2.2.2 Address NextHop Interface Metric Preference 2.2.2.2 192.168.0.2 eth0 0 0 quagga-pimd-router# T27 DONE Implement debug command test pim receive assert See also TODO T6: (S,G) Assert state machine. T28 DONE Bad IPv4 address family=02 in Join/Prune dump Reported by Andrew Lunn <andrew.lunn@ascom.ch> # 58-byte pim v2 Join/Prune dump # ------------------------------ # IPv4 address family=02 is wrong, correct IPv4 address family is 01 # See http://www.iana.org/assignments/address-family-numbers # c8XX YY03 : ip src 200.xx.yy.3 e000 000d : ip dst 224.0.0.13 9404 0000 : ip router alert option 148.4.0.0 2300 ab13 : pimv2,type=3 res=00 checksum=ab13 0200 : upstream family=02, encoding=00 c8XX YY08 : upstream 200.xx.yy.8 0001 00d2 : res=00 groups=01 holdtime=00d2 0200 0020 : group family=02, encoding=00, res=00, mask_len=20 ef01 0101 : group address 239.1.1.1 0001 0000 : joined=0001 pruned=0000 0200 0020 : source family=02, encoding=00, res=00, mask_len=20 0101 0101 : source address 1.1.1.1 T29 DONE Reset interface PIM-hello-sent counter when primary address changes See pim_ifp->pim_ifstat_hello_sent RFC 4601: 4.3.1. Sending Hello Messages Thus, if a router needs to send a Join/Prune or Assert message on an interface on which it has not yet sent a Hello message with the currently configured IP address, then it MUST immediately send the relevant Hello message without waiting for the Hello Timer to expire, followed by the Join/Prune or Assert message. T30 DONE Run interface DR election when primary address changes Reported by Andrew Lunn <andrew.lunn@ascom.ch> See pim_if_dr_election(). T31 If an interface changes one of its secondary IP addresses, a Hello message with an updated Address_List option and a non-zero HoldTime should be sent immediately. See also detect_secondary_address_change See also CAVEAT C15. See also RFC 4601: 4.3.1. Sending Hello Messages T32 FIXED Detection of interface primary address changes may fail when there are multiple addresses. See also CAVEAT C14. pim_find_primary_addr() should return interface primary address from connected list. Currently it returns the first address. Zebra daemon "show int" is able to keep the primary address as first address. T33 DONE Implement debug command: test pim receive upcall See also TODO T6: (S,G) Assert state machine. T34 DONE assert_action_a1 T35 DONE Review macros depending on interface I. See also: grep ,I\) pimd/*.c For the case (S,G,I) check if I is either 1) interface attached to this per-interface S,G state (don't think so) or 2) an arbitrary interface (most probably) For the arbitrary interface case (2), consider representing interface ifp as its primary address (struct in_addr ifaddr). The benefit is in_addr does not need to be dereferenced, so it does not demand protection against crashes. T36 DONE React to zebra daemon link-detect up/down notification. pim_ifp->primary_address is managed by detect_primary_address_change() depending on to ifp->connected (managed by zebra_interface_address_read()). T37 DONE Review list of variables which may affect pim_upstream.c pim_upstream_evaluate_join_desired(). Call pim_upstream_update_join_desired() accordingly. See the order of invokation: pim_if_dr_election(ifp); pim_if_update_join_desired(pim_ifp); /* depends on DR */ pim_if_update_could_assert(ifp); /* depends on DR */ pim_if_update_my_assert_metric(ifp); /* depends on could_assert */ join_desired depends on: pim_ifp->primary_address pim_ifp->pim_dr_addr ch->ifassert_winner_metric ch->ifassert_winner ch->local_ifmembership ch->ifjoin_state ch->upstream->rpf.source_nexthop.mrib_metric_preference ch->upstream->rpf.source_nexthop.mrib_route_metric ch->upstream->rpf.source_nexthop.interface T38 DONE Detect change in AssertTrackingDesired(S,G,I) See the order of invokation: dr_election: none update_join_desired: depends on DR update_tracking_desired: depends on DR, join_desired AssertTrackingDesired(S,G,I) depends on: pim_ifp->primary_address pim_ifp->pim_dr_addr ch->local_ifmembership ch->ifassert_winner ch->ifjoin_state ch->upstream->rpf.source_nexthop.interface PIM_UPSTREAM_FLAG_TEST_DR_JOIN_DESIRED(ch->upstream->flags) T39 DONE AssertTrackingDesired: flags is not matching evaluation # show ip pim assert-internal CA: CouldAssert ECA: Evaluate CouldAssert ATD: AssertTrackingDesired eATD: Evaluate AssertTrackingDesired Interface Address Source Group CA eCA ATD eATD eth0 192.168.1.100 1.1.1.1 239.1.1.1 no no no yes # T40 Lightweight MLDv2 http://tools.ietf.org/html/draft-ietf-mboned-lightweight-igmpv3-mldv2-05 http://www.ietf.org/internet-drafts/draft-ietf-mboned-lightweight-igmpv3-mldv2-05.txt http://www.ietf.org/html.charters/mboned-charter.html T41 DONE ssmping support See also: http://www.venaas.no/multicast/ssmping/ draft-ietf-mboned-ssmping-07 http://tools.ietf.org/html/draft-ietf-mboned-ssmping-07 Example: debug ssmpingd conf t ip ssmpingd 1.1.1.1 show ip ssmpingd T42 Static igmp join fails when loading config at boot time ! Wrong behavior seen at boot time: ! 2010/02/22 08:59:00 PIM: igmp_source_forward_start: ignoring request for looped MFC entry (S,G)=(3.3.3.3,239.3.3.3): igmp_sock=12 oif=eth0 vif_index=2 ! Correct behavior seen later: ! 2010/02/22 09:03:16 PIM: igmp_source_forward_start: ignoring request for looped MFC entry (S,G)=(2.2.2.2,239.2.2.2): igmp_sock=17 oif=lo vif_index=1 ! To see the wrong message at boot: ! debug igmp trace ! interface lo ip igmp ip igmp join 239.2.2.2 2.2.2.2 ip igmp join 239.3.3.3 3.3.3.3 ! ! Interfaces indexes: Interface Address ifi Vif PktsIn PktsOut BytesIn BytesOut eth0 200.202.112.3 2 2 0 0 0 0 lo 127.0.0.1 1 1 0 0 0 0 T43 PIM Neighbor Reduction https://datatracker.ietf.org/doc/draft-wijnands-pim-neighbor-reduction/ "In a transit LAN (no directly connected source or receiver), many of the PIM procedures don't apply. (...) This proposal describes a procedure to reduce the amount of neighbors established over a transit LAN." T44 Single Stream Multicast Fast Reroute (SMFR) Method https://datatracker.ietf.org/doc/draft-liu-pim-single-stream-multicast-frr/ "This document proposes an IP multicast fast convergence method based on differentiating primary and backup PIM join." T45 RFC5384 - The Join Attribute Format "This document describes a modification of the Join message that allows a node to associate attributes with a particular tree." T46 PIM Multi-Topology ID (MT-ID) Join-Attribute http://tools.ietf.org/html/draft-cai-pim-mtid-00 Depends on T45. "This draft introduces a new type of PIM Join Attribute used to encode the identity of the topology PIM uses for RPF." -x-