[TriLUG] Odd problem with RH8.0 box

[Peter Long]

Hi all,

I have been experiencing an intermittent problem with my trusty Linux 
box. Unfortunately I can't figure out the cause. The machine is running 
RedHat 8.0 and is a PII 350 with 384MB of RAM. It also has more then 
enough RAM. The box serves as my gateway to the Internet. It has two 
NICs and I am running IP Tables on it. I also use it as my mail server.

The symptoms of the problem are that every now and then it seems to 
"lock up". By that I mean that I cannot login at the console, neither 
via X or tty. The funny thing is that it still works fine as a router. 
My internal machines can still send traffic through it after it has 
locked up. At first I thought it was a problem with PAM since it locked 
up when I tried to login. Incidently IMAP from remote machines would 
also stop working as well as new SSH connections. Named also stops 
responding. I tried testing my theory that it was a PAM problem by 
leaving one tty console logged in after rebooting the system. However 
when the problem re-occurred I discovered that I could not do an 'ps' at 
the bash prompt. So it seems that you cannot launch new processes either.

There are no funny errors in the logs to indicate what the problem could 
be. Actually it seems to stop writing to the log entirely. I usually get 
an entry in the 'messages' log every 30 minutes from iptables for BOOTP 
traffic that is dropped. These stop occurring.

It does not seem to be a disk space or ram problem. I have gig free and 
230MB of the 384MB is unused.

Any clues or tips would be greatly appreciated.

--
Peter Long