The value of vRtrLdpGenGRNbrLiveTime specifies the value for neighbor
liveness timer. The amount of time the Label Switching Router (LSR)
keeps its stale label-FEC bindings is set to the lesser of the FT
Reconnect Timeout, as was advertised by the neighbor, and this local
timer, called the Neighbor Liveness Timer.
The LSR waits for the specified time till a LDP session re-establishes
itself. If within that time the LSR still does not establish an LDP
session with the neighbor, all the stale bindings are deleted. This
object has meaning only when vRtrLdpGenGracefulRestart is 'true'.