Patent ID: 8533171

Claim:
A method for file lock recovery in a distributed computer system, comprising: executing a distributed computer system having a plurality of nodes comprising a cluster; initiating a fail over for a network file system server from one node of the cluster to an adoptive node of the cluster; incrementing a cluster wide migration counter; pausing lock processing on the network file system; stopping file lock services at the adoptive node; restarting file lock services at the adoptive node, wherein the restart causes the adoptive node to commence a grace period for other network file system clients to connect to the adoptive node and reclaim file locks; after restarting file lock services, updating a cluster file system on the adoptive node with process identifiers; selectively resuming network file system file lock recovery requests on the adoptive node during the grace period; decrementing the cluster wide migration counter; resuming file lock services at the adoptive node after NFS file lock recovery has completed; and resuming lock processing on the network file system if the counter is zero.