wbwd(4) [freebsd man page]

WBWD(4) 						   BSD Kernel Interfaces Manual 						   WBWD(4)

NAME

     wbwd -- device driver for watchdog timer found on Winbond Super I/O chips

SYNOPSIS

     To compile this driver into the kernel, place the following line in your kernel configuration file:

	   device wbwd

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

	   wbwd_load="YES"

DESCRIPTION

     The wbwd driver provides watchdog(4) support for the watchdog interrupt timer present on at least the following Winbond Super I/O chips:

     o	 83627HF/F/HG/G Rev. G
     o	 83627HF/F/HG/G Rev. J
     o	 83627HF/F/HG/G Rev. UD-A
     o	 83627DHG IC ver. 5

SYSCTL VARIABLES

     The wbwd driver provides the following options as sysctl(8) variables.

     dev.wbwd.0.timeout_override
	     This variable allows to program the timer to a value independent on the one provided by the watchdog(4) framework while still relying
	     on the regular updates from e.g.  watchdogd(8).  This is particularly useful if your system provides multiple watchdogs and you want
	     them to fire in a special sequence to trigger an NMI after a shorter period than the reset timeout for example.  The value set must
	     not be lower than the sleep time of watchdogd(8).	A value of 0 disables this feature and the timeout value provided by watchdog(4)
	     will be used.

     dev.wbwd.0.debug_verbose
	     If set this sysctl will tell the driver to log its current state before and after the timer reset on each invocation from watchdog(9)
	     to the kernel message buffer for debugging.

     dev.wbwd.0.debug
	     This read-only value gives the state of some registers on last update.

     The wbwd driver also provides further sysctl options that are hidden by default.  See the source code for more information.

SEE ALSO

     watchdog(4), device.hints(5), watchdog(8), watchdogd(8), watchdog(9)

HISTORY

     The wbwd driver first appeared in FreeBSD 10.0.

AUTHORS

     This manual page was written by Bjoern A. Zeeb <bz@FreeBSD.org>.

BSD
								 December 28, 2012							       BSD

WD_KEEPALIVE(8) 					      System Manager's Manual						   WD_KEEPALIVE(8)

NAME

       wd_keepalive - a simplified software watchdog daemon

SYNOPSIS

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

DESCRIPTION

       This is a simplified version of the watchdog daemon. If configured so it only opens
	.IR  /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 com-
       piled 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.

OPTIONS

       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 /etc/watchdog.conf.

FILES

       /dev/watchdog
	      The watchdog device.

       /var/run/wd_keepalive.pid
	      The pid file of the running wd_keepalive.

SEE ALSO

       watchdog.conf(5)

       watchdog(8)

4th Berkeley Distribution					   January 2005 						   WD_KEEPALIVE(8)