Configuring OSPF Graceful Restart
OSPF GR involves the following:
IETF standard GR—Uses Opaque LSAs to implement GR.
Non IETF standard GR—Uses link local signaling (LLS) to advertise GR capability and uses out of band synchronization to synchronize the LSDB.
A device can act as a GR Restarter and GR Helper at the same time.