BFD parameters must be configured on the ingress before a BFD session is established to monitor an LDP LSP.
The system view is displayed.
A BFD session is bound to a dynamic LSP.
The local discriminator of the BFD session is set.
The remote discriminator of the BFD session is set.
The local discriminator of a local device and the remote discriminator of a remote device must be the same, and the remote discriminator of the local device and the local discriminator of the remote device must be the same. A discriminator inconsistency causes BFD session establishment failures.
A BFD session is allowed to modify the port state table or link state table.
If the BFD session on a trunk or VLAN member interface allows BFD to modify the PST, and a BFD session is configured on the main interface, you must configure the wait to restore (WTR) time for the BFD session that monitors the main interface. This prevents the BFD session on the main interface from flapping when the member interface joins or leaves the main interface.
The local minimum interval at which BFD packets are sent is set.
When the reverse tunnel is an IP link, the local parameters cannot be configured.
Effective local interval at which BFD packets are sent = MAX { Locally configured minimum interval at which BFD packets are sent, Remotely configured minimum interval at which BFD packets are received }
Effective local interval at which BFD packets are received = MAX { Remotely configured interval at which BFD packets are sent, Locally configured interval at which BFD packets are received }
Local detection interval = Local interval at which BFD packets are received x Remote BFD detection multiplier
For example, the locally configured interval at which BFD packets are sent is 200 ms, the interval at which BFD packets are received is 300 ms, and the detection multiplier is 4. The remotely configured interval at which BFD packets are sent is 100 ms, the interval at which BFD packets are received is 600 ms, and the detection multiplier is 5.
The effective local interval at which BFD packets are sent is 600 ms (MAX { 200 ms, 600 ms }), the effective local interval at which BFD packets are received is 300 ms (MAX { 100 ms, 300 ms }), and the detection interval is 1500 ms (300 ms x 5).
The effective remote interval at which BFD packets are sent is 300 ms (MAX { 100 ms, 300 ms }), the effective remote interval at which BFD packets are received is 600 ms (MAX { 200 ms, 600 ms}), and the detection interval is 2400 ms (600 ms x 4).
The local minimum interval for receiving BFD packets is set.
When the reverse tunnel is an IP link, the local parameters cannot be configured.
The local BFD detection multiplier is set.
The configurations are committed.