Symptom, Analysis, Solution – H3C Technologies H3C S12500 Series Switches User Manual
Page 199: Rps cannot join spt in pim-sm
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6.
Check that the same PIM mode is enabled on all the routers in the entire network. Make sure that
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 is 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.
Analysis
•
As the core of a PIM-SM domain, the RPs provide services for specific multicast groups. Multiple RPs
can coexist in a network. Make sure that the RP information on all routers is exactly the same, and
a specific group is mapped to the same RP. Otherwise, multicast forwarding will fail.
•
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 will fail.
Solution
1.
Use the display ip routing-table command to verify that a route is available on each router to the
RP.
2.
Use the display pim rp-info command to verify that the 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.