RPC.STATD(8) | System Manager's Manual | RPC.STATD(8) |
rpc.statd
— host
status monitoring daemon
rpc.statd |
[-d ] |
rpc.statd |
[-d ] -n |
rpc.statd |
[-d ] [-l |
-L | -N
hostname] |
The rpc.statd
utility is a daemon which
cooperates 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 restarts, the
statd.notify
service will be started to notify all
of the hosts which were being monitored at the time of the crash.
The rpc.statd
utility consists of two
launchd(8)-controlled services. The
statd.notify
service is run whenever the system
needs to notify remote hosts of a restart. The statd
service is controlled by
rpc.lockd(8) so that the
rpc.statd
daemon is running whenever
rpc.lockd(8) is running.
The following is a list of command line options that are
available. Note that since rpc.statd
is normally
started by launchd(8), configuration
of these options should be controlled using the equivalent settings in the
NFS configuration file. See
nfs.conf(5) for a list of tunable
parameters.
-d
nfs.statd.verbose
option in
nfs.conf(5).
Logging is performed via
syslog(3) using the LOG_DAEMON
facility. By default, only messages up to priority LOG_WARNING are
logged. Setting the verbose level to one will add LOG_NOTICE messages
which includes logging failed mount attempts. A verbose level of two
will increase the log level to LOG_INFO which includes logging
successful mount attempts. A log level of three or more will add
LOG_DEBUG messages and cause increasing amounts of debug information to
be logged. The debug information exposes lots of information about
rpc.statd
's inner workings which is typically
only useful to developers. Note: the
syslog(8) configuration may need to
be adjusted in order to see the increased verbosity.
The following command line option causes the daemon to run in the
statd.notify
notification service mode:
-n
The remaining command line options may be useful for viewing or modifying the contents of the status file. They do not start up any daemon or service.
statd
daemon.statd.notify
daemon.statd.notify
service's property list file for
launchd(8).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
pause and re-try notification at frequent intervals for 10 minutes, then
hourly, and finally gives up after 24 hours. The -N
option may be used to remove the "needs notification" status from
such hosts.
The protocol requires that symmetric monitor requests are made to both the local and remote daemon in order to establish a monitored relationship. This is convenient for the NFS locking protocol, but probably reduces the usefulness of the monitoring system for other applications.
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
July 5, 2008 | macOS 14.6 |