Hardware failure -- how to find out?

[Cassiano Leal <cassianol@dbserver.com.br>]

People,

I have at work a mixed system Debian sarge/etch running a firewall and 
vpn server on a K6-2.

Today, we were experiencing some connectivity problems, and we found out 
that they were caused by iptables not initiating properly and 
segfaulting. So, I went into the servers room, to find out that the 
computer in question was beeping constantly, which led me to believe it 
was a hardware failure.

The computer wouldn't respond to 'init 6' via ssh, so I tried to 
Ctrl-Alt-Delete locally, without success. Tried to login, again to fail.

So, the solution was to hit the power button and expect it to work. To 
my luck, it did straight away and we are at the moment working without a 
problem.

But I couldn't yet state what have caused the problem. So, my question 
is: how do I trace this failure? Log files? Which ones?

Any other tests I can run?

Please, bear in mind that this is a production firewall system.

I thank you all in advance.

Cheers,
Cassiano Leal