Use the show ip pim pending
command to display the pending joins on a PIM router. A pending join can be an IGMPv2 join (host join) or PIM (*,G) or (S,G) join (PIM router joins, PIM-SM only) received by a router for which there is no active multicast flow to satisfy the received join. This aids in determining what flows are being requested on the PIM network, but for which there is no data. If data availability is expected for a flow, and a join for that flow is showing as pending, this moves the troubleshooting search to the source of the flow since the routers are verified to be seeing the request for data.
Syntax:
Displays the joins received on the switch from downstream devices that want to join a specified (*,G) or (S,G) multicast group (flow) address or all multicast groups known on the switch.
A join remains in a pending state until traffic is received for the flow. The VLAN (PIM interface) on which each join was received is also displayed.
Example Show IP PIM pending command
Syntax:
Displays the joins received on the switch from downstream devices that want to listen to the multicast traffic in all (*,G) or (S,G) multicast groups (flows) that a specified RP address or all RPs in the domain are responsible for. A join remains in a pending state until traffic is received for the flow. The VLAN (PIM interface) on which each join was received is also displayed.