Protocol Independent Multicast NSR for IGMP

Junos OS extends PIM nonstop active routing (NSR) support to IGMP-only interfaces by mapping multicast joins on these interfaces to PIM states and replicating those states to the backup Routing Engine. With the relevant PIM state available on the backup, multicast routes are maintained in a forwarding state, ensuring continuity during a Routing Engine switchover. This capability enables uninterrupted multicast traffic flow by preserving join and route information across failover. The enhancement supports IGMPv2 and IGMPv3 environments.