You can enable interface status association using the process-interface-status command in the BFD session view. When the BFD session status changes, the Line protocol current state field is Up (BFD Status Down) in the display this interface command output on the interface. At the same time, the RM withdraws the host routes and network segment routes on the interface.
Application scenario: BFD for IFNET is usually applied to the scenario where a Layer 2 device exists between two routers, or there are transmission devices, or a single fiber fault occurs.