PIM-SM is enabled on all routers, and each router has discovered an RP. You want to check that the router has joined the desired multicast groups.
Look at the Join messages to see the groups for which the PIM router maintains join state:
aviva@RouterA> show pim join Instance: PIM.master Family: INET Group: 224.0.1.39 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Group: 224.0.1.40 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Group: 224.1.1.1 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Group: 224.1.1.1 Source: 10.0.15.1 Flags: sparse Upstream interface: fe-0/0/1.0 Group: 224.2.127.254 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Group: 230.0.1.1 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Instance: PIM.master Family: INET6
The extensive version of this command gives the details for each multicast group:
aviva@RouterA> show pim join extensive 224.1.1.1 Instance: PIM.master Family: INET Group: 224.1.1.1 Source: * RP: 192.168.13.1 Flags: sparse,rptree,wildcard Upstream interface: local Upstream neighbor: Local Upstream State: Local RP Downstream Neighbors: Interface: se-0/0/3.0 10.0.16.2 State: Join Flags: SRW Timeout: 165 Group: 224.1.1.1 Source: 10.0.15.1 Flags: sparse Upstream interface: fe-0/0/1.0 Upstream neighbor: 10.0.15.1 Upstream State: Local Source, Local RP Keepalive timeout: 116 Downstream Neighbors: Interface: se-0/0/3.0 10.0.16.2 State: Join Flags: S Timeout: 165
When a host connected to a PIM router informs the router that it wants to receive traffic from a multicast group, the PIM router sends (S,G) Join messages out its RPF interfaces to inform the next upstream router that it wants to receive packets for that group. Each upstream router repeats this process until this branch of the multicast tree reaches the router directly connected to the multicast source or reaches a router that already has multicast forwarding state for the (S,G) pair.
The show pim join command lists all groups the router has sent Join messages to and has successfully joined. The output in this recipe indicates that RouterA has joined six multicast groups. For each group, you see the multicast source of the group. This is either the IP address of a source router or an asterisk (*)if the Join message is directed toward any source. The RP line shows the address of the rendezvous point for the group, and Upstream interface is the routers interface toward the groups source.
The extensive version of the command shows the upstream state, which is information about the upstream router, and downstream interfaces toward the multicast receiver.
The output of the show pim join extensive command for group 224.1.1.1 agrees with the route information displayed with the show multicast route extensive command (explained in Recipe 16.9):
aviva@RouterA> show multicast route extensive Address family INET Group: 224.1.1.1 Source: 10.0.15.1/32 Upstream interface: fe-0/0/1.0 Downstream interface list: se-0/0/3.0 Session description: ST Multicast Groups Statistics: 0 kBps, 0 pps, 5 packets Next-hop ID: 359 Upstream protocol: PIM Route state: Active Forwarding state: Forwarding Cache lifetime/timeout: 356 seconds Wrong incoming interface notifications: 0
The information these two commands displays is subtly different. The show multicast route command describes forwarding plane information, while the show pim join command covers the control plane. The information in the two commands should agree, but each command shows some information that the other does not.
Recipe 16.9
Router Configuration and File Management
Basic Router Security and Access Control
IPSec
SNMP
Logging
NTP
Router Interfaces
IP Routing
Routing Policy and Firewall Filters
RIP
IS-IS
OSPF
BGP
MPLS
VPNs
IP Multicast