ps -axf core dump strangeness

Louis Mandelstam (
Thu, 12 Dec 1996 14:03:39 +0200 (SAT)

Hello -

This one is getting to me and it's being quite a nuisance, so I'm really
hoping someone can help me see what I'm missing:

I've got a production server running Red Hat 4.0, with all updates, and
kernel 2.0.27 - the problem also showed itself under 2.0.25 - these are
the only two kernels I've run on the machine, so I can't say of older
kernels behaved.

The system seems to get into a "state" where typing 'ps -axf' will dump

ps -af, ps -ax, ps -xf, ps -uxf etc etc all work just fine. Only 'ps
-axf' causes a seg fault.

This will go on for a while, then when I try quite a bit later, the
problem will be completely gone.

This is procps-1.01-7 from Red Hat.

It *may* be that the problem is related to certain times of the day -
starting in the morning, and going away at night. *If* this is the case,
it could be either temperature or load related. Since I've no clue what
could be happening, I can't go into that any further.

It hasn't been going on that long (new machine) so I can't be certain.

Everything else on the machine is working fine - it's doing some heavy
fileserving (NFS and Samba as well as some TFTP), sendmail is running
perfectly, kernel compiles work fine etc etc.

There *is* one other strangeness however - some daemons have been dying
silently every so often.

The only daemons that have done it to my knowledge have been bootpd and
apcd. This happens infrequenctly, maybe once every 3-4 days but still
hard to say.

Now core files are to be found when daemons die like this.

Any clues please?

If I can get something to convince me it might be a heat related problem,
I'll look into that - somewhat invasive but so is the problem itself.
It's just that everything else works so well - I find it hard to believe a
hardware level problem would cause 'ps -axf' to segfault, but not 'ps
-xf' etc - (the ps story is well tested)


L.Mandelstam - System Administrator
S A Council of Churches, PO Box 4921, Johannesburg, 2000, South Africa
tel:+27-11-492-1380 x114 fax:+27-11-492-1448 mobile: +27-83-229-0712