Copyright (c) 2003 Sean M. Kelly <smkelly@FreeBSD.org>
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$FreeBSD$
.Dd September 2, 2006 .Dt WATCHDOGD 8 .Os .Sh NAME .Nm watchdogd .Nd watchdog daemon .Sh SYNOPSIS .Nm .Op Fl d .Op Fl e Ar cmd .Op Fl I Ar file .Op Fl s Ar sleep .Op Fl t Ar timeout .Sh DESCRIPTION The .Nm utility interfaces with the kernel's watchdog facility to ensure that the system is in a working state. If .Nm is unable to interface with the kernel over a specific timeout, the kernel will take actions to assist in debugging or restarting the computer.
p If .Fl e Ar cmd is specified, .Nm will attempt to execute this command with .Xr system 3 , and only if the command returns with a zero exit code will the watchdog be reset. If .Fl e Ar cmd is not specified, the daemon will perform a trivial file system check instead.
p The .Fl s Ar sleep argument can be used to control the sleep period between each execution of the check and defaults to one second.
p The .Fl t Ar timeout specifies the desired timeout period in seconds. The default timeout is 16 seconds.
p One possible circumstance which will cause a watchdog timeout is an interrupt storm. If this occurs, .Nm will no longer execute and thus the kernel's watchdog routines will take action after a configurable timeout.
p Upon receiving the .Dv SIGTERM or .Dv SIGINT signals, .Nm will first instruct the kernel to no longer perform watchdog checks and then will terminate.
p The .Nm utility recognizes the following runtime options: l -tag -width ".Fl I Ar file" t Fl I Ar file Write the process ID of the .Nm utility in the specified file. t Fl d Do not fork. When this option is specified, .Nm will not fork into the background at startup. .El .Sh FILES l -tag -width ".Pa /var/run/watchdogd.pid" -compact t Pa /var/run/watchdogd.pid .El .Sh SEE ALSO .Xr watchdog 4 , .Xr watchdog 8 , .Xr watchdog 9 .Sh HISTORY The .Nm utility appeared in .Fx 5.1 . .Sh AUTHORS .An -nosplit The .Nm utility and manual page were written by .An Sean Kelly Aq smkelly@FreeBSD.org and .An Poul-Henning Kamp Aq phk@FreeBSD.org .
p Some contributions made by .An Jeff Roberson Aq jeff@FreeBSD.org .