BFD is bound to only the ingress node of an LDP LSP.
One LSP is bound to only one BFD session.
The detection only supports the LDP LSP that is triggered to establish by the host route.
The forwarding modes on the forwarding path and reverse path can be different (for example, an IP packet is sent from the source to the destination through an LSP, and is sent from the destination to the source in IP forwarding mode), but the forwarding path and reverse path must be established over the same link. If they use different links, BFD cannot identify the faulty path when a fault is detected.
Static BFD for LDP LSPs fast detect faults on an LDP LSP. Static BFD for LDP LSPs can be flexibly deployed, but needs to be manually controlled.
Before configuring static BFD to detect an LDP LSP, configure a local LDP session. For details, see Configuring Basic Functions of MPLS LDP.