MSDP Mesh Groups

When a group of MSDP speakers in a domain are meshed together, they can be configured as a mesh-group. An MSDP mesh group reduces flooding by ensuring that a mesh-group member does not have to forward SA messages to other group members, because the originator will forward it to all group members. If a member R of a mesh-group M receives an SA message from an MSDP peer that is also a member of mesh-group M, R does not flood or forward these messages. If the SA message passes the peer-RPF check, then R forwards the SA message to all members of mesh-group M.

If a member R of a mesh-group M receives an SA message from an MSDP peer that is not a member of mesh-group M, then R does the peer-RPF check first for the SA message. If the peer-RPF check fails, R drops it. If the SA message passes the peer-RPF check, then R forwards the SA message to all members of mesh-group M.

Each MSDP peer in the mesh group must be configured as such (a peer in the mesh group).