RPC.STATD(8)						    BSD System Manager's Manual 					      RPC.STATD(8)

NAME

     rpc.statd -- host status monitoring daemon

SYNOPSIS

     rpc.statd [-d]

DESCRIPTION

     The rpc.statd utility is a daemon which co-operates with rpc.statd daemons on other hosts to provide a status monitoring service.	The daemon
     accepts requests from programs running on the local host (typically, rpc.lockd(8), the NFS file locking daemon) to monitor the status of
     specified hosts.  If a monitored host crashes and restarts, the remote daemon will notify the local daemon, which in turn will notify the
     local program(s) which requested the monitoring service.  Conversely, if this host crashes and re-starts, when the rpc.statd re-starts, it
     will notify all of the hosts which were being monitored at the time of the crash.

     The following option is available:

     -d      Cause debugging information to be written to syslog, recording all RPC transactions to the daemon.  These messages are logged with
	     level LOG_DEBUG and facility LOG_DAEMON.  Error conditions are logged irrespective of this option, using level LOG_ERR.

     -n      Just send SM_NOTIFY messages to notify any hosts of a restart.  Do not start daemon.

     The rpc.statd utility must NOT be invoked by inetd(8) because the protocol assumes that the daemon will run from system start time.  Instead,
     it should be run from rc(8) after the network has been started.

FILES

     /var/db/statd.status	     non-volatile record of currently monitored hosts.
     /usr/include/rpcsvc/sm_inter.x  RPC protocol specification used by local applications to register monitoring requests.

SEE ALSO

     syslog(3), rc(8), rpc.lockd(8)

BUGS

     There is no means for the daemon to tell when a monitored host has disappeared permanently (eg. catastrophic hardware failure), as opposed to
     transient failure of the host or an intermediate router.  At present, it will re-try notification attempts at frequent intervals for 10 min-
     utes, then hourly, and finally gives up after 24 hours.

     The protocol requires that symmetric monitor requests are made to both the local and remote daemon in order to establish a monitored rela-
     tionship.	This is convenient for the NFS locking protocol, but probably reduces the usefulness of the monitoring system for other applica-
     tions.

     The current implementation uses more than 1Kbyte per monitored host in the status file (and also in VM).  This may be inefficient for NFS
     servers with large numbers of clients.

STANDARDS

     The implementation is based on the specification in X/Open CAE Specification C218, "Protocols for X/Open PC Interworking: XNFS, Issue 4",
     ISBN 1 872630 66 9

BSD
								September 19, 1995							       BSD