Troubleshooting Ipv6 Pim Configuration; Failure Of Building A Multicast Distribution Tree Correctly - 3Com MSR 50 Series Configuration Manual

Troubleshooting IPv6
PIM Configuration
Failure of Building a
Multicast Distribution
Tree Correctly
routing-table command to view the PIM routing table information on each
router. For example:
# View the IPv6 PIM multicast routing table information on Router A.
[RouterA] display pim ipv6 routing-table
Total 0 (*, G) entry; 1 (S, G) entry
(4001::100, FF3E::101)
Protocol: pim-ssm, Flag:
UpTime: 00:00:11
Upstream interface: Serial2/0
Upstream neighbor: 1002::2
RPF prime neighbor: 1002::2
Downstream interface(s) information:
Total number of downstreams: 1
1: Ethernet1/0
Protocol: mld, UpTime: 00:00:11, Expires: 00:03:25
The information on Router B and Router C is similar to that on Router A.
# View the IPv6 PIM multicast routing table information on Router D.
[RouterD] display pim ipv6 routing-table
Total 0 (*, G) entry; 1 (S, G) entry
(4001::100, FF3E::101)
Protocol: pim-ssm, Flag: LOC
UpTime: 00:08:02
Upstream interface: Ethernet1/0
Upstream neighbor: NULL
RPF prime neighbor: NULL
Downstream interface(s) information:
Total number of downstreams: 1
1: Serial2/0
Protocol: pim-ssm, UpTime: 00:08:02, Expires: 00:03:25
Symptom
None of the routers in the network (including routers directly connected with IPv6
multicast sources and receivers) has IPv6 multicast forwarding entries. That is, a
multicast distribution tree cannot be built correctly and clients cannot receive IPv6
multicast data.
Analysis
An IPv6 PIM routing entry is created based on an IPv6 unicast route, whichever
■
IPv6 PIM mode is running. Multicast works only when unicast does.
The RPF interface must support IPv6 PIM. An RPF neighbor must be an IPv6 PIM
■
neighbor as well. If IPv6 PIM is not enabled on the RPF interface or the RPF
neighbor, the establishment of a multicast distribution tree will surely fail,
resulting in abnormal multicast forwarding.

Troubleshooting IPv6 PIM Configuration

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