When a fault occurs on the SAP side, the pseudowire status bit is set for both active and standby pseudowires. When only one of the pseudowire is faulty, SMGR does not notify CFM. The notification occurs only when both pseudowire becomes faulty. The SMGR propagates the fault to CFM.
Because there is no fault handling in the pipe service, any CFM fault detected on an SDP binding is not used in the pseudowire redundancy’s algorithm to choose the most suitable SDP binding to transmit on.