I have been running on 11.1 U4 from May. In the past 1 week my server shuts down by itself. I have upgraded to U5 and also to 11.2 Beta 1 and the same issue persists. It happens at random times and essentially the server turns off. Once I power it on again I get an email that there was an unauthorized reboot. I don't see anything wrong in the logs. I have attached /var/log/messages content from the reboot I did yesterday to another reboot today. I have also attached the save debug file. I have been running this machine for almost 5 years and never had this happen. Can someone help on what could be wrong here?