10.3-stable random server reboots - finding the reason

[Matthew Seaman]

On 04/18/17 12:59, tech-lists wrote:
> I have an up-to-date 10.3 server that is randomly rebooting, after being
> up for days. Previously it had been up for many months. The problem is,
> nothing seems to be left in the logs to indicate why it's doing this. I
> have all.log and console.log enabled.
> 
> So, what I'm asking is, how can I capture its last gasp?
> 

Well, probably the most effective way to do that is to hook up a serial
cable and make a continuous log of the system console onto another
machine.  That's not guaranteed to get you good diagnostics though.

A server that spontaneously becomes unstable is often suffering from
hardware problems.  It could be all sorts of things -- one of the fans
died so it's overheating; the power supply is flaking out; capacitors on
the motherboard are giving up; memory has gone bad.  Many of these sort
of problems will result in an instant system crash with nothing in any
log files or on the console.

Start by trying out some hardware diagnostics, like running memtest86
for 24h or so.

	Cheers,

	Matthew

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