This machine has been acting very peculiar today—it was more or less inaccessible most of the morning. It was a very strange thing, too; when I sat down at the physical computer, I could reboot it, start tinkering, and everything would work fine for a minute or two. Then it would start getting slower and slower, eventually freezing up nearly completely. It bogged down fast enough that I wasn't even able to fire up any diagnostic software before it would lock up. I couldn't do any work on the machine directly, but I discovered that if I booted it up and accessed it only via ssh, I'd have maybe 30 minutes at a time before the creeping cruds would immobilize everything, so I was able to do a piece-by-piece backup of the essentials.

Then I discovered that if I unplugged the ethernet cable and rebooted, it worked fine. That's very suspicious. Now I've gone through and disabled all the absolutely non-essential network services, turned on the firewall, and everything seems to be cruising smoothly for now.

Any computer experts out there? Was I getting hit with a DOS attack or something? Mac OS X usually seems pretty resilient about that sort of thing, and shrugs off most of the worms and other nasties going around, but the way it was getting hammered into unusability briefly after going live onto the net was awfully suggestive.