URGENT: 6.1/amd64 server hangs

[Andrea Venturoli]

Hello.
A server I manage is locking too frequently.
The behaviour is very strange: almost nothing works, no daemon is 
running, keyboard is ignored, but still the machine will answer pings.

The real problem is that I'm not able to diagnose this, since no message 
is displayed on the console or recorded in the logs and no crash is 
produced. I compiled DDB in, I can press Ctrl-Alt-Esc and drop into it, 
but then again the keyboard won't work, so it's useless.

Although this box features a dual core CPU, I'm running with SMP 
disabled, so to leave this out of the way.
Apart from that, the most unusual things this box has are an amr 
controller (featuring RAID5) and GELI. Are there any known issues with 
these?

How is 6.2 stability right now? Dumping and upgrading is the only thing 
I can think about, though I'm not sure whether this would be an 
improvement...

Any other hint? Any info I should look for and provide?

  bye & Thanks
	av.