R3303-HP HSR6800 Routers IP Multicast Configuration Guide

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6. Verify that the same PIM mode is enabled on all the routers in the entire network. Make sure the
same PIM mode (PIM-SM or PIM-DM) is enabled on all routers. For PIM-SM, verify that the BSR and
RP configurations are correct.
Multicast data abnormally terminated on an intermediate
router
Symptom
An intermediate router can receive multicast data successfully, but the data cannot reach the last-hop
router. An interface on the intermediate router receives data but no corresponding (S, G) entry is created
in the PIM routing table.
Analysis
• If a multicast forwarding boundary has been configured through the multicast boundary command,
any multicast packet will be kept from crossing the boundary, and no routing entry can be created
in the PIM routing table.
• In addition, the source-policy command filters received multicast packets. If the multicast data fails
to pass the ACL rule defined in this command, PIM cannot create the route entry either.
Solution
1. Use the display current-configuration command to verify the multicast forwarding boundary
settings. Use the multicast boundary command to change the multicast forwarding boundary
settings.
2. Use the display current-configuration command to verify the multicast filter configuration. Change
the ACL rule defined in the source-policy command so that the source/group address of the
multicast data can pass ACL filtering.
RPs cannot join SPT in PIM-SM
Symptom
An RPT cannot be established correctly, or the RPs cannot join the SPT to the multicast source.
Analysis
• As the core of a PIM-SM domain, the RPs serve specific multicast groups. Multiple RPs can coexist
in a network. Make sure the RP information on all routers is exactly the same and that a specific
group is mapped to the same RP. Otherwise, multicast forwarding fails.
• If the static RP mechanism is used, the same static RP command must be executed on all the routers
in the entire network. Otherwise, multicast forwarding fails.
Solution
1. Use the display ip routing-table command to verify that a route to the RP is available on each
router.
2. Use the display pim rp-info command to verify that the dynamic RP information is consistent on all
routers.
3. Use the display pim rp-info command to verify that the same static RP address has been configured
on all the routers in the entire network.