The value of tmnxMsdpPeerGroupMode is used to configure groups of
peers in a full mesh topology.
MSDP peers can be grouped in a full-mesh topology that prevents
excessive flooding of source-active messages to neighboring peers.
When operating in meshed mode, source-active messages received from
a mesh group member are always accepted but are not flooded to other
members of the same mesh group. As a result, these source-active
messages are only flooded to non-mesh group peers or members of
other mesh groups.
By default 'standard' (non-meshed) mode is used.