MVPN upstream PE fast failover

MVPN upstream UMH fast failover is supported for P2MP SR PMSI, as illustrated in Figure: Example of MVPN upstream PE fast failover. The upstream PE failure detection uses the Unidirectional Forwarding Detection (UFD) method. A downstream PE (receiver PE) supports fast upstream failover using the capability:

• to select two UMH nodes
• to monitor the upstream PE health using UFD

The tunnel status is monitored using the UFD session status received over the P-tunnel; the C-flow source is declared to be active based on this monitoring information. If multiple nodes are sourcing C-flows, the receiver PE node can choose to receive traffic from a primary and a standby source, but forwards only the multicast stream received from the primary source. If the detected P-tunnel status is down, the multicast receiver PE forwards the traffic received over the standby P-tunnel.