Network lock manager

The network lock manager is a facility that works in cooperation with the Network File System (NFS) to provide a System V style of advisory file and record locking over the network.

The network lock manager (rpc.lockd) and the network status monitor (rpc.statd) are network-service daemons. The rpc.statd daemon is a user level process while the rpc.lockd daemon is implemented as a set of kernel threads (similar to the NFS server). Both daemons are essential to the ability of the kernel to provide fundamental network services.