How to use Linux software watchdog?

linux linux-kernel busybox watchdog
Verve Innovation picture Verve Innovation · Jan 31, 2012 · Viewed 82.6k times · Source

Can anybody tell me how to handle the software watchdog in Linux?

I have a program SampleApplication which runs continuously and I need to restart it if its hangs or closes unexpectedly.

I was Googling about this and found Linux has watchdog at /dev/watchdog but don’t know how to use it. Could someone help me with an example?

My question is where to I specify my application name and delay interval to restart?

Answer

nope picture nope · Feb 23, 2012

Since the moderators ignore post-improvements now i'll have to post it seperately

The linux software watchdog will reboot the machine, not just restart your process.

Well this is simply not true, it is very possible to restart single or multiple processes after the watchdog signals that the systems is hanging - you can even ABORT the reboot or do a SOFT-reboot, one is able to configure "test" and "repair"-scripts / binaries which do whatever you want them to do. The busybox-version of watchdog is stripped down to a near-unusable level ... i guess the world will never know why the busybox-devs decided to abandon primary functionalities - for now, it would be best to avoid busybox at all --> the speed-improvements are nearly inexistent, the size-decrease does not compensate the huge loss of functionality. /bin/bash is rather small - recompile everything with the flag "-Os" if size matters and you're good to go - an out-of-the-box watchdog which allows for just about everything one could want.

Oh and PLEASE do NOT create your own watchdog - that'll most likely leave you with unhandled errors and make your life bad one day.

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