3Com S7902E, Руководство по настройке

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2) Check the multicast filter configuration. Use the display current-configuration command to
check 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 Unable to Join SPT in PIM-SM
Symptom
An RPT cannot be established correctly, or the RPs cannot join the SPT to the multicast source.
Analysis
z
As the core of a PIM-SM domain, the RPs serve 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.
z
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) Check that a route is available to the RP. Carry out the display ip routing-table command to
check whether a route is available on each router to the RP.
2) Check the dynamic RP information. Use the display pim rp-info command to check whether the
RP information is consistent on all routers.
3) Check the configuration of static RPs. Use the display pim rp-info command to check whether the
same static RP address has been configured on all the routers in the entire network.
RPT Establishment Failure or Source Registration Failure in PIM-SM
Symptom
C-RPs cannot unicast advertise messages to the BSR. The BSR does not advertise bootstrap
messages containing C-RP information and has no unicast route to any C-RP. An RPT cannot be
established correctly, or the DR cannot perform source register with the RP.
Analysis
z
The C-RPs periodically send C-RP-Adv messages to the BSR by unicast. If a C-RP has no unicast
route to the BSR, the BSR cannot receive C-RP-Adv messages from that C-RP and the bootstrap
message of the BSR will not contain the information of that C-RP.
z
In addition, if the BSR does not have a unicast router to a C-RP, it will discard the C-RP-Adv
messages from that C-RP, and therefore the bootstrap messages of the BSR will not contain the
information of that C-RP.
z
The RP is the core of a PIM-SM domain. Make sure that the RP information on all routers is exactly
the same, a specific group G is mapped to the same RP, and unicast routes are available to the
RP.
Solution
1) Check whether routes to C-RPs and the BSR are available. Carry out the display ip routing-table
command to check whether routes are available on each router to the RP and the BSR, and
whether a route is available between the RP and the BSR. Make sure that each C-RP has a unicast