China Mobile China Mobile Centec Centec Centec Inesa SAIA In systems with redundant control plane processors, Bidirectional Forwarding Detection (BFD) sessions are typically managed by a single active processor. When that processor fails and a standby takes over, BFD sessions may be interrupted long enough for remote peers to declare failure, even though the forwarding plane remains operational. This document describes requirements and operational considerations for preserving BFD sessions across control plane switchover events. It discusses how BFD session state can be maintained on a standby processor and how BFD processing can be resumed by the standby within the BFD Detection Time, without requiring cooperation from or signaling to remote BFD peers.