Configuring LDP GR helper
By default LDP GR is disabled. You can globally enable it. When LDP GR enabled, the router waits until it receives an LDP Initialization message from its neighbor to know whether it must delete its states or start the LDP GR recovery procedure. Also, LDP GR is applicable to all LDP sessions regardless of the adjacency type that exists between the neighbors.
vyatta@R1# set protocols mpls-ldp graceful-restart helper-enable