This guide is about how to setup watchdog in Ubuntu.

Enable Watchdog

For Ubuntu V180531 the watchdog is enabled by default. However, for newer versions it’s disabled by default. You can use the following commands to enable it.

$ sudo ln -s  /lib/systemd/system/watchdog.service /etc/systemd/system/multi-user.target.wants/watchdog.service
$ sudo systemctl enable watchdog.service
$ sudo systemctl start watchdog.service

Tip: You need to create the service link manually, due to a debian bug.

Setup Watchdog Timeout

The default timeout is 10S, you can change it in /etc/watchdog.conf.

$ sudo vim /etc/watchdog.conf

Modify watchdog-timeout to change the timeout.

Restart watchdog service.

$ sudo systemctl restart watchdog

Test Watchdog

Trigger a Kernel crash.

$ sudo -i
root@Khadas:~# echo c > /proc/sysrq-trigger 

If watchdog setup successfully, the system will reboot after the timeout you set above.

Disable Watchdog

$ sudo systemctl disable watchdog