Hello everyone - My CentOS 6.8 server has been rebooting itself every 2 to 4 hours for the last several days. I do not know where to look for logs that might give a clue what the problem is. There are no unusual entries in /var/log/messages. I looked over other log files in /var/log and found nothing suggestive. Where else can I look? By luck I saw the beginning of a reboot on the server console. Normally I have other systems up on the KVM switch. It appears to have dumped core. I don't know where to look for the core dump files. They are not in /root. The problem started while the server was still 6.7. It had almost 290 days of uptime when the problem started. I have tried the following, none of which made any difference. I ran the upgrade to 6.8. I tried stopping non-essential services two at a time. I ran MemTest 86+. No memory errors were found. I turned off swap. I unplugged the USB hard drive that I use to hold daily and weekly backups. It was being recognized as /dev/sda for some reason. Lm_sensors shows the processor running between 45 and 50C. Hddtemp shows the hard drives running between 35 and 40C. LM_Sensors does not produce valid data on fan speed, but a visual check shows all fans running normally and no build-up of dust. The system is behind a big UPS that runs several other systems. The UPS log file does not record any power failures and none of the other systems are rebooting at random. What else can I look at? Thanks - Bill Gee