RPC.STATD(8) BSD System Manager's Manual RPC.STATD(8)
rpc.statd -- host status monitoring daemon
rpc.statd 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 spec-
ified hosts. If a monitored host crashes and restarts, the remote daemon
will notify the local daemon, which in turn will notify the local pro-
gram(s) which requested the monitoring service. Conversely, if this host
crashes and restarts, when rpc.statd restarts, it will notify all of the
hosts which were being monitored at the time of the crash.
Options and operands available for rpc.statd :
-d The -d option causes debugging information to be written to sys-
log, recording all RPC transactions to the daemon. These mes-
sages are logged with level LOG_DEBUG and facility LOG_DAEMON.
Error conditions are logged irrespective of this option, using
The rpc.statd daemon must NOT be invoked by inetd(8) because the protocol
assumes that the daemon will run from system start time. Instead, it
should be configured in rc.conf(5) to run at system startup.
/var/db/statd.status non-volatile record of currently moni-
/usr/include/rpcsvc/sm_inter.x RPC protocol specification used by local
applications to register monitoring
syslog(3), rc.conf(5), rpc.lockd(8)
The implementation is based on the specification in X/Open CAE Specifica-
tion C218, "Protocols for X/Open PC Interworking: XNFS, Issue 4", ISBN 1
872630 66 9
A version of rpc.statd appeared in SunOS 4.
There is no means for the daemon to tell when a monitored host has disap-
peared permanently (e.g., catastrophic hardware failure), as opposed to
transient failure of the host or an intermediate router. At present, it
will retry notification attempts at frequent intervals for 10 minutes,
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 relation-
ship. This is convenient for the NFS locking protocol, but probably
reduces the usefulness of the monitoring system for other applications.
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.
BSD September 19, 1995 BSD