Random reboots with FreeBSD-7 STABLE

[Roland Smith]

On Tue, Mar 10, 2009 at 08:07:47PM +0100, Ralf Folkerts wrote:
> Roland Smith wrote:
> 
> Hi Roland,
> 
> thanks for your reply!
> 
> [...]
> >> It *always* happens when I'm "in" X; usually while using firefox3. It 
> >> may not happen 7 days but then three days in a row.
> >>     
> > [...]
> > Sounds like hardware trouble.
> >  
> > It could be a dying powersupply, or a loose cable. If you have a spare
> > powersupply, swap it out. Or have it tested instead. Sometimes checking
> > if all the cables are connected properly might help.
> >   
> Well, when the System crashed the 2nd or 3rd time I did reset all 
> Connectors and RAM. I might try another PS, though.
> 
> However, as mentioned, the same machine runs nicely with Kubuntu 
> 8.10/amd64. Now, I do know this is is everything but a "proof" that the 
> Hardware is OK; however, to me this is is kind of "indicator" that the 
> problem might be lying "more" on the FreeBSD-side than on the 
> Hardware-side. 

Different operating systems sometimes stress the hardware in different
ways. In my experience both FreeBSD and Linux have a way of exposing
flaky hardware. And remember that correlation doesn't imply causation!

> Thanks again; as mentioned I will swap PSs (have an identical one in 
> another machine) - however, I'm afraid this won't solve the 
> crashes/reboots :-(

In my limited experience with them it seems to me that kernel
programming errors are more prone to result in a kernel panic than in a
straight reboot or hang. The latter are more an indication of
e.g. unstable voltages or excessive temperatures.

Another avenue of investigation might be to install a system monitor
like mbmon(1) and have log temperatures and especially voltages to
another machine or synchronously written logfile every second. So you
_might_ catch it if the PSU is flaky. Then again, a flaky PSU will
likely die on you in the not too distant future anyway.

One thing to look out for is environmental contaminants in the PSU. I
work for a company that makes carbon fiber reinforced products. We loose
several PSU's (and some electric motors) each year, probably due to
filaments of (conductive) carbon fiber getting into them and causing
shorts. Last week my CAD workstation died with an impressive
bang. Luckily the damage was limited to the PSU, and it didn't fry the
motherboard. 

Roland
-- 
R.F.Smith                                   http://www.xs4all.nl/~rsmith/
[plain text _non-HTML_ PGP/GnuPG encrypted/signed email much appreciated]
pgp: 1A2B 477F 9970 BA3C 2914  B7CE 1277 EFB0 C321 A725 (KeyID: C321A725)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-amd64/attachments/20090310/e2a37452/attachment.pgp