1WD_KEEPALIVE(8)             System Manager's Manual            WD_KEEPALIVE(8)
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NAME

6       wd_keepalive - a simplified software watchdog daemon
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SYNOPSIS

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

12       This  is  a simplified version of the watchdog daemon. If configured so
13       it only opens
14        .IR /dev/watchdog , and keeps writing to it often enough to  keep  the
15       kernel  from resetting, at least once per minute. Each write delays the
16       reboot time another minute. After a minute of inactivity  the  watchdog
17       hardware  will  cause a reset. In the case of the software watchdog the
18       ability to reboot will depend on the state of the machines  and  inter‐
19       rupts.
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21       The  wd_keepalive daemon can be stopped without causing a reboot if the
22       device /dev/watchdog is closed correctly, unless your  kernel  is  com‐
23       piled with the CONFIG_WATCHDOG_NOWAYOUT option enabled.
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25       Under  high system load wd_keepalive might be swapped out of memory and
26       may fail to make it back in in  time.  Under  these  circumstances  the
27       Linux  kernel will reset the machine. To make sure you won't get unnec‐
28       essary reboots make sure you have the variable realtime set to  yes  in
29       the  configuration  file watchdog.conf.  This adds real time support to
30       wd_keepalive: it will lock itself into memory and there should   be  no
31       problem even under the highest of loads.
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33       On system running out of memory the kernel will try to free enough mem‐
34       ory by killing process. The wd_keepalive daemon itself is exempted from
35       this so-called out-of-memory killer.
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OPTIONS

38       Available command line options are the following:
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40       -c config-file, --config-file config-file
41              Use config-file as the configuration file instead of the default
42              /etc/watchdog.conf.
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FILES

45       /dev/watchdog
46              The watchdog device.
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48       /var/run/wd_keepalive.pid
49              The pid file of the running wd_keepalive.
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SEE ALSO

52       watchdog.conf(5)
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54       watchdog(8)
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584th Berkeley Distribution        January 2005                  WD_KEEPALIVE(8)
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