[colug-432] Debian server strangeness

[Robert Grimm]

I admin a Debian server that primarily runs Squid. A few weeks ago, there was a power outage that was longer than the UPS could handle. The server went down and came back up as usual. Nobody told me for a while that the web filtering wasn't working because the managers don't have filtering and the other users don't like it. It was about a week and a half before I noticed that something was wrong. 

The server was forwarding everything that hit it as usual. What it wasn't doing was responding to any requests except ping. I could do a port scan and see all the correct open ports, but I couldn't access the web interface or ssh. I rebooted it a few times and it always came back up with the same problems. I configured the router so that the server didn't have to be there and brought it home to my network. As soon as I changed its IP address to work on my network, everything worked. I can ssh in, I can access the web interface, and Squid is working. I have no idea what happened. Does anyone have any idea what could have caused this and what I might be able to do to prevent it in the future?