As with unicast routing protocols, there are a number of multicast routing protocols, each with its own advantages and disadvantages. In gated, support for DVMRP, MOSPF, and Dense mode and Sparse mode PIM are anticipated. Currently, only Dense mode PIM is completed. All of these protocols rely on IGMP.
This configuration simply enables IGMP and PIM on all interfaces. The default mode for PIM is dense mode.
#
igmp yes ;
#
pim yes ;
If you want to enable tracing of IGMP and PIM packets and log when Multicast Forwarding Cache entries are added and delete, use the following configuration:
traceoptions "/tmp/gated.log" replace route ;
#
igmp yes {
traceoptions normal packets;
} ;
#
pim yes {
traceoptions normal route packets;
} ;
If you are running PIM in the presence of tunneled DVMRP and the gated multicast kernel then PIM will try to run over the tunnel pseudo interfaces. They should be disabled as follows:
#
igmp yes ;
#
pim yes {
interface tu disable ;
} ;
#