SA redistribution and filtering
Redistribution and filtering is used to control SA flooding. The
MSDP redistribute policy is applied on the MSDP node that originates
the SAs to control which SAs are advertised on all MSDP peers. An
SA filter is applied to a specific MSDP peer in the inbound direction
or outbound directions or both inbound and outbound direction on any
MSDP router. Filtering is multicast group based.
When configuring MSDP redistribution, use prefix lists to create the route polices. When a route
policy is created it must match the group prefix with the name of the prefix list
created for the group address. If deny action is set for the lists in the route-policy,
the policy blocks the matching groups from all the sources. If permit action is set for
the lists in the route-policy, the policy accepts the matching groups from all the
sources. MSDP redistribution does not refer to the redistribution of SPB domain sources
to MSDP. MSDP redistribution refers to SAs which needs to be redistributed to other MSDP peers.
Note
MSDP redistribution is applied globally to all MSDP peers. SA filtering is used
to filter SAs on a peer-to-peer level.