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       wd_keepalive - a simplified software watchdog daemon


       wd_keepalive [-c filename|--config-file filename]


       This  is  a  simplified  version  of the watchdog daemon. It only opens
       /dev/watchdog, and keeps writing to it often enough to keep the  kernel
       from  resetting, at least once per minute. Each write delays the reboot
       time another minute. After a minute of inactivity the watchdog hardware
       will cause a reset. In the case of the software watchdog the ability to
       reboot will depend on the state of the machines and interrupts.

       The wd_keepalive daemon can be stopped without causing a reboot if  the
       device  /dev/watchdog  is  closed  correctly,  unless  your  kernel  is
       compiled with the CONFIG_WATCHDOG_NOWAYOUT option enabled.

       Under high system load wd_keepalive might be swapped out of memory  and
       may  fail  to  make  it  back in in time. Under these circumstances the
       Linux kernel will reset  the  machine.  To  make  sure  you  won’t  get
       unnecessary reboots make sure you have the variable realtime set to yes
       in the configuration file watchdog.conf.  This adds real  time  support
       to  wd_keepalive:  it will lock itself into memory and there should  be
       no problem even under the highest of loads.

       On system running out of memory the kernel  will  try  to  free  enough
       memory  by  killing process. The wd_keepalive daemon itself is exempted
       from this so-called out-of-memory killer.


       Available command line options are the following:

       -c config-file, --config-file config-file
              Use config-file as the configuration file instead of the default


              The watchdog device.

              The pid file of the running wd_keepalive.