watchdog timer retrigger
watchdogd is a daemon to activate and
periodically retrigger the
watchdog(4) timer device from userland.
watchdogd is designed to work in high load
environments, where other methods (such as a shell script invoking
sysctl(8)) would involve too much overhead.
The basic premise is that after every
resets the hardware timer to period. See also
watchdog(4) for more information on how watchdog timers work.
The options are as follows:
- Do not daemonize. If this option is specified,
watchdogdwill run in the foreground.
- Specify how often, in seconds,
watchdogdshould retrigger the hardware timer. If no interval is specified, the value of period (see below) divided by three is used.
- 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 halt(8).
- Set the hardware timer to expire in period seconds. The default is 30 seconds.
- Be quiet. With this option specified,
watchdogdwill not output a warning message if the underlying hardware adjusted the timeout period.
watchdogd program first appeared in
watchdogd was written by