When configuring MVPN extranets, remember
the following considerations:
If there is more than one VRF routing instance on a provider
edge (PE) router that has receivers interested in receiving multicast
traffic from the same source, virtual tunnel (VT) interfaces must
be configured on all instances.
For auto-RP operation, the mapping agent must be configured
on at least two PEs in the extranet network.
For asymmetrically configured extranets using auto-RP,
when one VRF instance is the only instance that imports
routes from all other extranet instances, the mapping agent must be
configured in the VRF that can receive all RP discovery messages from
all VRF instances and mapping-agent election should be disabled.
For bootstrap router (BSR) operation, the elected BSR
must be on a PE router that is configured with one extranet instance
and that instance must import routes from all VRF instances in the
extranet.
RSVP-TE point-to-multipoint LSPs must be used for the
provider tunnels.
PIM dense mode is not supported in the MVPN extranets
VRF instances.
