The value of tmnxMsdpPeerGrpPeerMaxActSrcs specifies the
maximum number of source active messages that will be accepted by
MSDP peer group peer. This effectively controls the number of active
sources that can be stored on the system.
By default, no limit is placed on the number of source active messages
and this is specified by the value '-1'. A value of
0 means that no source active messages will be accepted.