Technical Tip: Understanding the log message 'FortiGate had experienced an unexpected power off!'

[iskandar_lie]

Description	This article explains the typical circumstances behind the "FortiGate had experienced an unexpected power off!" log message.
Scope	All versions of FortiGate.
Solution	In the event of a power failure, FortiGate will log the event: 27: date=2022-10-26 time=03:40:12 eventtime=1666780811810286720 tz="-0700" logid="0100032009" type="event" subtype="system" level="information" vd="root" logdesc="FortiGate started" msg="Fortigate started" 41: date=2022-10-26 time=03:40:12 eventtime=1666780759530689524 tz="-0700" logid="0100032200" type="event" subtype="system" level="critical" vd="root" logdesc="Device shutdown" msg="Fortigate had experienced an unexpected power off!"  The message will be reported by FortiGate once the device is powered back on. If FortiGate has rebooted unexpectedly, this message may also be logged. Use the COMLog feature and wait for the issue will happen again to discover why the FortiGate was rebooted. Related documents: Technical Tip: How to use COMLog feature Technical Tip: Displaying logs via FortiGate's CLI