WATCHDOGD(8)

NAME
watchdogd - watchdog daemon

SYNOPSIS
watchdogd [-dnw] [--debug] [--softtimeout] [--softtimeout-action action] [--pretimeout timeout] [--pretimeout-action action] [-e cmd] [-I file] [-s sleep] [-t timeout] [-T script_timeout]

DESCRIPTION
The watchdogd utility interfaces with the kernel's watchdog facility to ensure that the system is in a working state. If watchdogd is unable to interface with the kernel over a specific timeout, the kernel will take actions to assist in debugging or restarting the computer.

If -e cmd is specified, watchdogd will attempt to execute this command with system(3), and only if the command returns with a zero exit code will the watchdog be reset. If -e cmd is not specified, the daemon will perform a trivial file system check instead.

The -n argument 'dry-run' will cause watchdog not to arm the system watchdog and instead only run the watchdog function and report on failures. This is useful for developing new watchdogd scripts as the system will not reboot if there are problems with the script.

The -s sleep argument can be used to control the sleep period between each execution of the check and defaults to 10 seconds.

The -t timeout specifies the desired timeout period in seconds. The default timeout is 16 seconds.

One possible circumstance which will cause a watchdog timeout is an interrupt storm. If this occurs, watchdogd will no longer execute and thus the kernel's watchdog routines will take action after a configurable timeout.

The -T script_timeout specifies the threshold (in seconds) at which the watchdogd will complain that its script has run for too long. If unset script_timeout defaults to the value specified by the -s sleep option.

Upon receiving the SIGTERM or SIGINT signals, watchdogd will first instruct the kernel to no longer perform watchdog checks and then will terminate.

The watchdogd utility recognizes the following runtime options:

-I file
    Write the process ID of the watchdogd utility in the specified file.

-d --debug
    Do not fork. When this option is specified, watchdogd will not fork into the background at startup.

-w  Complain when the watchdog script takes too long. This flag will cause watchdogd to complain when the amount of time to execute the watchdog script exceeds the threshold of 'sleep' option.

--pretimeout timeout
    Set a "pretimeout" watchdog. At "timeout" seconds before the watchdog will fire attempt an action. The action is set by the --pretimeout-action flag. The default is just to log a message (WD_SOFT_LOG) via log(9).

--pretimeout-action action
    Set the timeout action for the pretimeout. See the section Timeout Actions.

--softtimeout
    Instead of arming the various hardware watchdogs, only use a basic software watchdog. The default action is just to log(9) a message (WD_SOFT_LOG).

--softtimeout-action action
    Set the timeout action for the softtimeout. See the section Timeout Actions.

Timeout Actions
The following timeout actions are available via the --pretimeout-action and --softtimeout-action flags:

panic
    Call panic(9) when the timeout is reached.

ddb Enter the kernel debugger via kdb_enter(9) when the timeout is reached.

log Log a message using log(9) when the timeout is reached.

printf
    call the kernel printf(9) to display a message to the console and dmesg(8) buffer.

Actions can be combined in a comma separated list as so: log,printf which would both printf(9) and log(9) which will send messages both to dmesg(8) and the kernel log(4) device for syslog(8).

FILES
/var/run/watchdogd.pid

SEE ALSO
watchdog(4), watchdog(8), watchdog(9)

HISTORY
The watchdogd utility appeared in FreeBSD 5.1.

AUTHORS
-nosplit The watchdogd utility and manual page were written by Sean Kelly <smkelly@FreeBSD.org> and Poul-Henning Kamp <phk@FreeBSD.org>.

Some contributions made by Jeff Roberson <jeff@FreeBSD.org>.

The pretimeout and softtimeout action system was added by Alfred Perlstein <alfred@freebsd.org>.