Thus sounds like the out of memory killer. You should find at least a few entries in the system log detailing what was killed and why. Where this is logged on a Debian system, I don't know. -- Deanna Earley ----- Reply message ----- From: "Keith Williams" <keithwilliamsnp(a)gmail.com> To: <users(a)lists.bitfolk.com> Subject: [bitfolk] Nagios warning Date: Wed, Apr 11, 2012 10:42 Yesterday I was away from the computer and came back to see a series of Nagios alerts, related to DNS. It appears that the Bitfolk dns servers were unable to update a zone from my server. I was unable to login to my server, so went into Xen. It was unable to either shutdown or reboot. When I opened a console window, it was impossible to read as text was scrolling up continuously and rapidly. I had no alternative but to Destroy. A scary option, but within seconds it did the trick and all is running well now. I have scanned the logs this morning trying to find out what had gone wrong. I realise it was something going haywire and consuming all the resources, but please could anyone give me pointers on how to determine what it was that was behaving so badly? Keith -- Keith Williams "If knowledge can create problems, it is not through ignorance that we can solve them." Isaac Asimov He's doing it again! www.justgiving.com/France-The-Wrong-Way Tailor Made English www.tmenglish.org