I have a raspberry pi 2 with original power supply (5v 2a) from farnell with raspbian. Tried more than 4 sd cards (lexar class 10, kingston class 8, trasncendet class 10) connected to the router via ethernet cable.

This rpi it's on a remote location only as a controller for ubiquiti AP.

For some reason that I can't figure out, some times after 2 or 3 days, some others, after 1 week, rpi suddenly stop / crashes and don´t answer via ssh or even no ping at all. I have to manually unplug / plug the power cord. I can't understand that if crash and boot and crash again, if don't even boot...

This is quite frustating, cause I have to go this location (drive more than 20km) just to unplug / plug the power cord.

Steps that I made without sucess: -install watchdog, but on daemon.log appears that it's not doing nothing at all cause miss /dev/watchdog

Nov  1 23:27:15 raspberrypi watchdog[31974]: starting daemon (5.12):
Nov  1 23:27:15 raspberrypi watchdog[31974]: int=1s realtime=yes sync=no soft=no mla=24 mem=0
Nov  1 23:27:15 raspberrypi watchdog[31974]: ping: no machine to check
Nov  1 23:27:15 raspberrypi watchdog[31974]: file: no file to check
Nov  1 23:27:15 raspberrypi watchdog[31974]: pidfile: no server process to check
Nov  1 23:27:15 raspberrypi watchdog[31974]: interface: no interface to check
Nov  1 23:27:15 raspberrypi watchdog[31974]: test=none(0) repair=none(0) alive=/dev/watchdog heartbeat=none temp=none to=root no_act=no
Nov  1 23:27:15 raspberrypi watchdog[31974]: cannot open /dev/watchdog (errno = 2 = 'No such file or directory')

Cause I don't find out out it's happening, can anyone help me to read logs in order to find what's happening?

  • I've edited your title to make this question more specific. Note we aren't a discussion forum (please have a closer look at the tour). You'll have to break this down into separate questions if you want an answer to all of them.
    – goldilocks
    Commented Nov 2, 2015 at 12:44

1 Answer 1


It's pretty clear about there being no /dev/watchdog.

You may have to manually load the driver. Try:

sudo modprobe bcm2708_wdog
sudo modprobe bcm2835_wdt

And see if /dev/watchdog now exists. If it doesn't, or there are errors, immediately check tail -n 25 /var/log/syslog and/or journalctl -xn 25 to see if there is any explanation.

You can also double check the modules are loaded:

lsmod | grep _wd

To load the modules at boot, add them to /etc/modules, i.e.,


You may only need to be explicit about the last one, bcm2708_wdog. If that fails, try tail -n 500 /var/log/syslog | grep wdog after booting.

  • 1
    When I do modprobe bcm2708_wdog, system creates /dev/watchdog, but after reboot, this file /dev/watchdog dissapears. But anyway, even with this watchdog enable, how can dig into the real problem that it's causing this?
    – plopes
    Commented Nov 2, 2015 at 12:30
  • Yes, that will not persist across reboots. It is pretty odd the service does not do this itself. I've added a bit at the end about how to load them/it automatically. If by "real problem" you mean the crashing/going offline thing, that's a separate and more complex issue.
    – goldilocks
    Commented Nov 2, 2015 at 12:41
  • 1
    OK I add bcm2708_wdog to etc/modules, and after reboot the file at /dev/watchdog remains. Thanks for that @goldilocks. But I still want to dig to what really makes all of this. Wich logs or what can I do to get this needle?
    – plopes
    Commented Nov 2, 2015 at 12:47
  • 1
    /var/log/syslog should contain everything. You'll notice that the first message from boot is from rsyslogd indicating start, then messages from the kernel recognizable by the timestamp format -- seconds since start to six decimal places. This makes a boot easy to find by searching for the string 0.000000. Immediately before this stuff you'll find whatever messages were left before shutdown. Normally the last one should be rsyslogd exiting; if you pulled the plug that won't have happened, but there may be clues about why the system went offline or froze up.
    – goldilocks
    Commented Nov 2, 2015 at 12:52
  • I will dig... hope with this watchdog helps to prevent frozen state. Once I saw a program for noobs like me that we could upload our syslog and check errors...
    – plopes
    Commented Nov 2, 2015 at 13:42

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