My server has been running Ubuntu Server 12.04 LTS up until last week. Last week I did some hardware upgrades (new PSU and chassis) and proceed to do a clean install of Ubuntu Server 12.04. The installation was perfect; however, as I proceed to install OpenSSH, the system completely crashed. The monitor turned off, I could not SSH in, and the server's power button (when held for 10s) would not power down the machine. I attempted to do Alt-SysRq R-E-I-S-U-B, but was unable to restart the system. I had to yank the power cord. I then re installed Ubuntu Server and was confronted by the same issue.
Today I installed LMDE XFCE to see if somehow that would resolve the issue. It installed but the issue remained. I don't have much experience with these types of issues and would greatly appreciate any help! I have attached log files.
P.S. I was barely able to get these log files, the system crashed about a minute later. (up for about 5 minutes total)