[GTALUG] mysterious restarts

[Bob Jonkman]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Did you check the mainboard for popped capacitors? Anything that's
between 5-10 years old could still be suffering from the capacitor
plague. That would account for the sudden onset and now-consistent
failures.

https://en.wikipedia.org/wiki/Capacitor_plague

- --Bob.


On 2016-06-14 11:10 AM, D. Hugh Redelmeier via talk wrote:
> We have a computer that started doing random and frequent restarts
> on the weekend.  We don't know why.
> 
> Any suggestions?
> 
> It looks as if the power dips momentarily and the computer
> reboots, with no message that we have observe.  But it could just
> as easily be a crash of some other kind that leaves no trace.
> 
> The system is an HP Compaq Pro 6300 Small Form Factor PC running 
> Fedora 20.
> 
> The crash seems to be at different points (i.e. not one consistent 
> software activity).  The crashes don't seem correlated with heavy 
> workloads (eg. it crashed a couple of times while I was staring at
> log files to see if there was any hint of the problem).
> 
> Hypothesis: a Fedora 20 bug.  But the software has not been changed
> in months.  Updates have not been appled this year.  Since the
> behaviour has changed without the software changing, I don't think
> that Fedora is to blame.
> 
> Hypothesis: it might be heat-related (the room it is in gets warm).
> I vacuumed out the interior and defuzzed the heat sinks.  This did
> not improve the uptime.
> 
> Hypothesis: it might be contact-related.  So I disconnected and 
> reconnected most internal connectors and reseated the memory. This
> did not seem to improve the uptime.
> 
> Hypothesis: it might be the power supply.  Normally, I'd swap
> power supplies to test this hypothesis but this Small Form Factor
> computer has a unique (and probably expensive) power supply.  I
> opted to move the disk to a Dell OptiPlex 990 Small Form Factor
> computer and use that.
> 
> The Dell, with the HP's disk, seems stable.  No rebooting.  This is
> in the same warm room, but the weather has changed.
> 
> In the original HP box, I installed a disk that I had laying around
> (a 60G drive from a discarded laptop), installed Ubuntu 16.04, and
> have been running four CPU-bound processes for 24 hours.  No crash.
> I admit that this is in a cooler room.  The heat and power load of
> a laptop drive is less than that of a 3.5" HDD, but I would not
> think that that is significant.
> 
> The computer is a couple of years old but still has a year of 
> warranty.  There are confidential files on the disk drive so I'd
> like to narrow down the problem before calling in HP support.
> Asking for a particular replacement part is more convenient that
> shipping the computer back to HP. --- Talk Mailing List 
> talk at gtalug.org https://gtalug.org/mailman/listinfo/talk
> 


- --
Bob Jonkman <bjonkman at sobac.com> Phone: +1-519-635-9413
SOBAC Microcomputer Services http://sobac.com/sobac/
Software --- Office & Business Automation --- Consulting
GnuPG Fngrprnt:04F7 742B 8F54 C40A E115 26C2 B912 89B0 D2CC E5EA


-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
Comment: Ensure confidentiality, authenticity, non-repudiability

iEYEARECAAYFAldgItsACgkQuRKJsNLM5eqQtQCeKScb/G9mNhVJDtLId7xtYz2Y
oTkAnRplr3GRssf8YkMp6IPL5TqLetlL
=w0Y0
-----END PGP SIGNATURE-----