Multicast Routing - Misc

In this post i detail some of the plethora of multicast commands that may be of use...

config-if#ip igmp access-group {acl}

interface command that delimits the multicast groups that the hosts are allowed to join.

config-if#ip igmp limit {n}
interface command that limits the number of groups that users on an interface may join

config-if#ip igmp join-group
joins multicast group with process switching

config-if#ip igmp static-group
joins multicast group with fast switching

ip pim spt-threshold {n}
specifies the threshold that must be reached before moving to the spt

ip multicast rate-limit in out group-list {x} {y}
Controls transmission rate TO a multicast group
where x is the acl matches the multicast groups
where y is the bandwidth statement

ip multicast-boundary
Implements a bidirectional boundary for multicast traffic
The following example shows how to set up a boundary for all administratively scoped addresses:

access-list 1 deny 239.0.0.0 0.255.255.255
access-list 1 permit 224.0.0.0 15.255.255.255
interface ethernet 0
ip multicast boundary 1


ip multicast cache-headers
Enables history of multicast traffic through the router.
Can be viewed with show ip mpacket

Router_2#s ip mpacket
IP Multicast Header Cache
11 packets received over 00:00:24, cache size: 1024 entries
Key: id/ttl timestamp (name) source group

0015/254 180.476 (?) 1.1.1.1 225.0.0.1
0071/15 181.336 (?) 5.5.5.5 224.0.1.39
0016/254 182.472 (?) 1.1.1.1 225.0.0.1