MPLS LSP Ping

MPLS LSP ping can be used to diagnose the state of label-switched paths (LSPs), including LDP-signaled LSPs. Based on how the LSP outbound (egress) node at the remote endpoint of the connection replies to the probes, you can determine the connectivity of the LSP. Each probe is an echo request sent to the LSP exit point as an MPLS packet with a UDP payload. If the outbound node receives the echo request, it checks the contents of the probe and returns a value in the UDP payload of the response packet. If the device receives the response packet, it reports a successful ping response. Responses that take longer than 2 seconds are identified as failed probes.