The statd daemon
The Network Status Monitor provides application processes with host status
information. The SCO NFS Network Status Monitor
is the daemon statd. statd runs on both client
and server in such a way that client and server monitor their own status
and that of each other.
To effect properly monitored locks, lockd relies upon notification of host state changes from the local statd. When the client statd detects a client crash, it notifies the server statd of the state change so that the server can release any locks it is holding for the client. When the server crashes, its local statd notifies the client statd of the state change; the client statd informs the local lockd and lockd reclaims any existing locks established on the server.
For a detailed description of the sequence of events involved in the interaction of the Network Lock Manager and the Network Status Monitor during locking, crash, recovery, and unlocking, see the standards outlined in the Common Applications Environment (CAE) specification Protocols for X/Open Internetworking: XNFS. For further information on the daemon statd, see the statd(NADM) manual page.