remote computer acting weird

albright · Posted: Thu Jun 19, 2014 6:04 pm Post subject: remote computer acting weird

Hi all - a remote computer that I leave running for various reasons has
started acting in a strange fashion.

First, it has twice now frozen, requiring a visit from someone local
to reboot it (no gui is running by the way).

Currently, it is up but exhibiting these symptoms:

the "ps axf" command hangs with no output and can't be killed with
ctrl-c or kill -9

the "top" command with "c" command hangs similarly ...

I suspect a hardware (memory ??) fault but if anyone has advice it would
be welcome.
_________________
.... there is nothing - absolutely nothing - half so much worth
doing as simply messing about with Linux ...
(apologies to Kenneth Graeme)

eccerr0r · Posted: Thu Jun 19, 2014 11:42 pm Post subject:

Normally when I run into these spontaneous hang issues at the command line (or in GUI, doesn't matter) is usually a motherboard issue. When there's a memory or cpu issue, I tend to get segfaults.

Was there a recent kernel upgrade that could have triggered this?
_________________
Intel Core i7 2700K/Radeon R7 250/24GB DDR3/256GB SSD
What am I supposed watching?

albright · Posted: Fri Jun 20, 2014 11:53 am Post subject:

thanks for the reply;

I upgrade the kernel regularly but can't say that the problem
was triggered by any particular upgrade (its worth dialing
back the kernel however - I'll give that a try)

I ran (remotely) the user space memtester program on
4gb of memory and the computer locked up after
a while (did not show any memory error; just froze
and I was emerging something at the same time)

the computer is only about 3 years old (Asus p8p67
motherboard with approved memory)
_________________
.... there is nothing - absolutely nothing - half so much worth
doing as simply messing about with Linux ...
(apologies to Kenneth Graeme)

russK · l33t Joined: 27 Jun 2006 Posts: 665

Check dmesg regularly. I've had things freeze when there was a hard drive issue. Try smartmon tools. I believe there are some pretty good live CD's loaded with diagnostic tools but of course that would require physical access.

HTH

i92guboj · Posted: Fri Jun 20, 2014 2:23 pm Post subject:

It could be, virtually, anything.

I don't think there's an easy way to diagnose it from distance. Note that even some static electricity in the motherboard can turn it crazy. It happened to me several times over the years, and just touching the motherboard magically fixed it.

In any case, watch the logs, and try reverting to a previous kernel version. But it smells like either hardware or something nasty that has been implanted into the system.