Server restarts by itself but you do not find any expected errors in iLO logs. In Syslogs (/var/log/messages), the following errors are present:
systemd-logind: Power key pressed
systemd-logind: Powering Off...
A Lithium related function would not cause a reboot of the server. Such instances are related to either hardware or manual intervention. We suggest that you check hardware or system for accidental power off. Also running "syswatch" as root user could help identify any hardware issues of iLo interface to check the same.
Here is a possible article from RedHat explaining this: Server shutdown/reboot with "Power key pressed" messages. Since the full article from RedHat can only be accessed by registered users, a copy of the same is attached to this knowledge article. The resolution steps from the Redhat article are reproduced as below:
- Check if the system has been deliberately powered off.
- Contact the hardware/hypervisor to check the administration console for shutdown, errors or related logs.