With Raspberry Pi, you can build nice things, but sometimes it is hanging around (sdcard, power supply, ...).

To avoid such a state, I recommend to install Watchdog.

Here are my notes for debian 7.9 on Rasberry Pi B+

Install the Software:

apt-get update
apt-get dist-upgrade
rpi-update
reboot
apt-get install watchdog sendmail-bin

ls /etc/rc2.d/S0*watchdog
update-rc.d watchdog disable
ls /etc/rc2.d/S0*watchdog

modprobe bcm2708_wdog
echo "bcm2708_wdog" | tee -a /etc/modules
lsmod | grep bcm2708_wdog

 

Configure Watchdog as you need: /etc/watchdog.conf

#ping			= 192.168.223.254
#file			= /tmp/easyiot.log
#change                  = 600
watchdog-timeout = 10 max-load-1 = 12 min-memory = 1 watchdog-device = /dev/watchdog pidfile = /var/run/watchdog.pid realtime = yes priority = 1

 

Test it!!!

 

Enable it:

ls /etc/rc2.d/S0*watchdog
update-rc.d watchdog defaults
ls /etc/rc2.d/S0*watchdog
reboot

 

Test it again:

tail -f /var/log/syslog

 

Note:

There is a bug in debian watchdog startscript, which produces error message on watchdog restart.
But this is not a problem when booting the pi:

watchdog[2021]: cannot open /dev/watchdog (errno = 16 = 'Device or resource busy')