Hard Hang, nothing in logs / no panics

Kris Kennaway kris at obsecurity.org
Fri May 11 21:47:36 UTC 2007


On Fri, May 11, 2007 at 04:43:06PM -0500, Roger Miranda  wrote:
> 
> > You missed that the debugger is there to debug bugs (including
> > deadlocks).  Break to the debugger and obtain the necessary debugging
> 
> I should've been more clear.  I can not break to the debugger (CTRL-ALT-ESC) 
> when the system locks up.

You may need the KDB_STOP_NMI option, especially if it is an SMP
system.  I forget if you also need to enable a sysctl on 6.x (look at
sysctl -a | grep nmi for the obvious one)

> Am I possible looking at a hardware issue?  If so 
> what is the best way to test for it?

If that doesn't work then in my experience it is likely to be
hardware-related.  The usual debugging procedure then involves trying
to replicate on an unrelated machine, and/or swapping out hardware
components.

Kris


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