xref: /dragonfly/usr.sbin/watchdogd/watchdogd.8 (revision 25a2db75)
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3.\" Copyright (c) 2005 Marc Balmer <mbalmer@openbsd.org>
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17.Dd October 4, 2009
18.Dt WATCHDOGD 8
19.Os
20.Sh NAME
21.Nm watchdogd
22.Nd watchdog timer retrigger daemon
23.Sh SYNOPSIS
24.Nm
25.Op Fl dnq
26.Op Fl i Ar interval
27.Op Fl p Ar period
28.Sh DESCRIPTION
29.Nm
30is a daemon to activate and periodically retrigger the
31.Xr watchdog 4
32timer device from userland.
33.Nm
34is designed to work in high load environments,
35where other methods
36(such as a shell script invoking
37.Xr sysctl 8 )
38would involve too much overhead.
39.Pp
40The basic premise is that
41after every
42.Ar interval
43seconds,
44.Nm
45resets the hardware timer to
46.Ar period .
47See also
48.Xr watchdog 4
49for more information on how watchdog timers work.
50.Pp
51The options are as follows:
52.Bl -tag -width Ds
53.It Fl d
54Do not daemonize.
55If this option is specified,
56.Nm
57will run in the foreground.
58.It Fl i Ar interval
59Specify how often, in seconds,
60.Nm
61should retrigger the hardware timer.
62If no interval is specified,
63the value of
64.Ar period
65(see below)
66divided by three is used.
67.It Fl n
68Do not restore the watchdog to its original values once it has been activated.
69With this set, the system will be rebooted by the watchdog even after a
70.Xr halt 8 .
71.It Fl p Ar period
72Set the hardware timer to expire in
73.Ar period
74seconds.
75The default is 30 seconds.
76.It Fl q
77Be quiet.
78With this option specified,
79.Nm
80will not output a warning message if the underlying hardware adjusted the
81timeout period.
82.El
83.Sh SEE ALSO
84.Xr watchdog 4 ,
85.Xr sysctl 8
86.Sh HISTORY
87The
88.Nm
89program
90first appeared in
91.Dx 2.5 .
92.Sh AUTHORS
93.Nm
94was written by
95.An Marc Balmer Aq mbalmer@openbsd.org .
96