Re: Troubleshooting OpenBSD hangs

[Dylan Smith <dylan_(_at_)_iompost_(_dot_)_co_(_dot_)_im>]

On Friday 19 December 2003 10:04 pm, Simon Hollier wrote:
> On Fri, 2003-12-19 at 16:44, Jason Haag wrote:
> > AFAI understood the OP, it's not a crash (ddb>) but a hang. I have the
> > same symptom here on a i386/3.4-stable (GENERIC) box. Every few days it
> > just freezes up.
> >
> > I have redirected the console to a serial port, and I see the boot
> > process there, can log in, etc.
> >
> > But the system freeze does not produce any output. The cursor on the
> > directly attached monitor/keyboard still blinks, but there no response
> > to keyboard input. Same on the serial console. No replies to ping. No
> > connection on port 22.

> I have seen this when a motherboard has problems.  It will work for a
> while and then just freeze.   Works for a while..freeze.  The console
> freezes, network freezes, serial console freezes.  For what it's worth,
> we use OpenBSD 3.x on quite a handful of machines and never a
> hang/crash.

I have seen this behaviour in a Compaq PC (Pentium-3 desktop class) that had 
power save features turned on in the BIOS. The system was used as a 
firewalling bridge. After a while, the network would fail as the machine 
simply stopped responding. (The console still responded, and as soon as you 
pressed Enter, the machine would magically spring back to life. However, if 
you ran X11, if the 'sleep' event happened, the only way of getting the 
machine back was to power it off and on again - the console would go blank 
and you couldn't switch VC or get any other response from the machine).

Checking the power light on the front showed it to be blinking. Disabling BIOS 
powersaving features fixed the problem.