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Re: [LUG] Dozing server

 

James Wonnacott wrote:
> I have a strange problem with a server which seems to doze off for 5 
> minutes or so once in a while.
> 
> Its fairly old (4 years) running Mandrake 10.0,  2.6.3 kernel
> 
> Every 15 minutes or so it refuses (or drops existing) connections (smtp, 
> pop3, ssh) pings become slow (anything from 1-100ms). tailing syslog or 
> messages suggests that nothing is happening, top shows nothing special. 
> then after about 5 minutes it just comes back and pretends nothing 
> happened. pings to it return in <1ms and all is fine and dandy again.
> 
> Any ideas.....

Probably something hardware related- I would guess that something is on 
the way out and therefore some operation fails every so often, and it 
keeps retrying until it eventually times out.

It probably isn't a program taking too much CPU (though that is a 
possibility), since it would have to be running at very high priority to 
make that much of an issue and nothing shows in top anyway. It's 
probably a kernel module- try unloading and stopping everything and 
running on the most basic setup you can and see if it still does it.

I recently had a problem with my server where it would just freeze every 
so often or get stuck due to hardware problem. I opened it up and the 
capacitors on the mobo were all failing, so I replaced that, but 
eventually worked out that the CPU was dead as well.

CPU/RAM/Mobo faults are impossible to diagnose.

Hope this helps
Simon

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