[mythtv-users] Need ideas for auto-recovery of locked up backend

[Simon Hobson]

Craig Huff wrote:
>Simon- are you talking about a watchdog timer that exists in the
>native hardware?  IIRC, such a timer exists in Intel CPUs.  Sadly, my
>system is based on an AMD Athlon CPU.  If I'm wrong, I'd gladly like
>more information on how to implement it with AMD CPUs.

Don't know if it's any help, but I spotted this on The Reg
http://forums.theregister.co.uk/forum/1/2013/04/22/dont_buy_without_ipmi/

Paul Crawford
System watchdog?
Quite a lot of ordinary motherboards have hardware watchdogs built in, for example the w83627 and similar chips that provide hardware monitoring (voltages, temperature, fan speeds, etc). This can provide a last-resort method of rebooting a sick server if you don't have lights-out support, but only SSH access.
With Linux you can add the corresponding watchdog driver module (they are black-listed by default in Ubuntu) and then the watchdog daemon and configure it to check a few vital signs. Typically you would check the load averages are not stupidly high (say over 5 per CPU core), maybe that rsyslogd is running, that you can run a simple bash script, etc.
If any of those tests fail then you get a moderately orderly reboot, and the hardware watchdog makes sure you get a reboot even if there is a kernel panic style of fault. Brutal perhaps, but it gets the system back up and hopefully either all OK again or at least you can SSH in to fix it.