No Sa Entries In The Router's Sa Cache; Inter-Rp Communication Faults In Anycast Rp Application - 3Com S7906E Configuration Manual

No SA Entries in the Router's SA Cache

Symptom
MSDP fails to send (S, G) entries through SA messages.
Analysis
The import-source command is used to control sending (S, G) entries through SA messages to
MSDP peers. If this command is executed without the acl-number argument, all the (S, G) entries
will be filtered off, namely no (S, G) entries of the local domain will be advertised.
If the import-source command is not executed, the system will advertise all the (S, G) entries of
the local domain. If MSDP fails to send (S, G) entries through SA messages, check whether the
import-source command has been correctly configured.
Solution
1) Check that a route is available between the routers. Carry out the display ip routing-table
command to check whether the unicast route between the routers is correct.
2) Check that a unicast route is available between the two routers that will become MSDP peers to
each other.
3) Check configuration of the import-source command and its acl-number argument and make sure
that ACL rule can filter appropriate (S, G) entries.

Inter-RP Communication Faults in Anycast RP Application

Symptom
RPs fail to exchange their locally registered (S, G) entries with one another in the Anycast RP
application.
Analysis
In the Anycast RP application, RPs in the same PIM-SM domain are configured to be MSDP peers
to achieve load balancing among the RPs.
An MSDP peer address must be different from the anycast RP address, and the C-BSR and C-RP
must be configured on different devices or interfaces.
If the originating-rp command is executed, MSDP will replace the RP address in the SA
messages with the address of the interface specified in the command.
When an MSDP peer receives an SA message, it performs RPF check on the message. If the
MSDP peer finds that the remote RP address is the same as the local RP address, it will discard
the SA message.
Solution
1) Check that a route is available between the routers. Carry out the display ip routing-table
command to check whether the unicast route between the routers is correct.
2) Check that a unicast route is available between the two routers that will become MSDP peer to
each other.
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