H3C Technologies H3C SecPath F1000-E - Manual (Page 674)

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• The same PIM mode must run on the entire network. Otherwise, the establishment of a multicast
distribution tree will surely fail, causing abnormal multicast forwarding.
Solution
1. Use the display ip routing-table command to verify that a unicast route exists from the receiver host
to the multicast source.
2. Use the display pim interface command to verify that that PIM is enabled on the interfaces,
especially on the RPF interface. If PIM is not enabled on the interface, use the pim dm or pim sm
command to enable PIM-DM or PIM-SM.
3. Use the display pim neighbor command to verify that the RPF neighbor is a PIM neighbor.
4. Verify that PIM and IGMP are enabled on the interfaces directly connecting to the multicast source
and to the receivers.
5. Use the display pim interface verbose command to verify that the same PIM mode is enabled on
the RPF interface and the corresponding interface of the RPF neighbor router.
6. Verify that the same PIM mode is enabled on all the routers in the entire network. Make sure the
same PIM mode is enabled on all the routers: PIM-SM on all routers, or PIM-DM on all routers. In
the case of PIM-SM, also check 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 therefore 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.