HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 164

Solution, Multicast data abnormally terminated on an intermediate router, Symptom, Analysis

Page 164 highlights

Solution 1. 2. 3. 4. 5. 6. Use the display ip routing-table command to verify that a unicast route exists from the receiver host to the multicast source. Use the display pim interface command to verify 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. Use the display pim neighbor command to verify that the RPF neighbor is a PIM neighbor. Verify that PIM and IGMP are enabled on the interfaces directly connecting to the multicast source and to the receivers. 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. Verify 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 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. 153

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153
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 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 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 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.