freeze

[Doug White]

On Fri, 10 Dec 2004, Aaron Stephanic wrote:

> I've had a server freeze three times on me know and I have no idea what
> the problem is... of course nothing gets output to the logs.  The first
> time it was at 3AM on a Sunday so I thought the problem must be one of
> the periodic scripts.  But those seemed fine when run by hand.  The
> second two times it was just after 11PM on a Thursday.  Does anyone know
> what could be running at that time?  This is a dual Xeon machine and the
> kernel and world were compiled with a pentium4 CPUTYPE, but I thought
> that could be the problem so the last time it froze I recompiled
> everything for i686.  But it froze again.  There are still some
> installed ports compiled for pentium4.  Now I'm thinking it could be
> PAE.  I'm using the PAE config file that ships with 5.3 with a few extra
> settings.  I think I'm going to disable that.  Is there any way I can
> get more information if/when it freezes next time?  Thanks.

If you have physical access to the box try compiling in DDB and hit
Ctrl-Alt-Esc on the keyboard when it freezes. If it drops into DDB then it
isn't a hard lockup, at least.  If you do get into ddb, capture the output
of the 'tr' command.

I'd also suggest setting up a serial console to capture any output that
may be occuring at the freeze point .. if you also compile with
BREAK_TO_DEBUGGER then you can trigger ddb from the serial console with a
serial break as well...

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite at gumbysoft.com          |  www.FreeBSD.org