H3C Technologies H3C SecPath F1000-E - Manual (Page 675)

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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 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.
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
• 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.
• 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.
• The RP is the core of a PIM-SM domain. Make sure 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. Use the display ip routing-table command to verify that routes are available on each router to the
RP and the BSR, and that a route is available between the RP and the BSR. Make sure each C-RP
has a unicast route to the BSR, the BSR has a unicast route to each C-RP, and all the routers in the
entire network have a unicast route to the RP.
2. PIM-SM needs the support of the RP and BSR. Use the display pim bsr-info command to verify that
the BSR information is available on each router, and then use the display pim rp-info command to
verify that the RP information is correct.
3. Use the display pim neighbor command to verify that normal PIM neighboring relationships have
been established among the routers.