.\" $OpenBSD: watchdogd.8,v 1.12 2007/04/16 07:46:54 mbalmer Exp $
.\"
.\" Copyright (c) 2005 Marc Balmer <mbalmer@openbsd.org>
.\"
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.\" purpose with or without fee is hereby granted, provided that the above
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.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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.Dd July 7, 2005
.Dt WATCHDOGD 8
.Os
.Sh NAME
.Nm watchdogd
.Nd watchdog timer retrigger daemon
.Sh SYNOPSIS
.Nm watchdogd
.Op Fl dnq
.Op Fl i Ar interval
.Op Fl p Ar period
.Sh DESCRIPTION
.Nm
is a daemon to activate and periodically retrigger the
.Xr watchdog 4
timer device from userland.
.Nm
is designed to work in high load environments,
where other methods
(such as a shell script invoking
.Xr sysctl 8 )
would involve too much overhead.
.Pp
The basic premise is that
after every
.Ar interval
seconds,
.Nm
resets the hardware timer to
.Ar period .
See also
.Xr watchdog 4
for more information on how watchdog timers work.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Do not daemonize.
If this option is specified,
.Nm
will run in the foreground.
.It Fl i Ar interval
Specify how often, in seconds,
.Nm
should retrigger the hardware timer.
If no interval is specified,
the value of
.Ar period
(see below)
divided by three is used.
.It Fl n
Do not restore the watchdog to its original values once it has been activated.
With this set, the system will be rebooted by the watchdog even after a
.Xr halt 8 .
.It Fl p Ar period
Set the hardware timer to expire in
.Ar period
seconds.
The default is 30 seconds.
.It Fl q
Be quiet.
With this option specified,
.Nm
will not output a warning message if the underlying hardware adjusted the
timeout period.
.El
.Sh SEE ALSO
.Xr watchdog 4 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
program
first appeared in
.Ox 3.8 .
.Sh AUTHORS
.Nm
was written by
.An Marc Balmer Aq mbalmer@openbsd.org .