Technical TIP: How to setup a recovery point by the backup partition.

The FortiGate hardware devices have two partitions in the flash.

The backup partition has the firmware before the last upgrade, which can recover while the primary system crashes.  There may be issues with the previous firmware that are not expected. 

There is a way to set the backup partition firmware version to the same as the primary partition:

1. After upgrading the FortiGate to the stable version, manually download the current firmware from the FortiCloud portal.
2. Upgrade the FortiGate with 'File Upload' by the image just downloaded.
3. After that, both partitions will show the same firmware version. The recovery point is set up.

From the above steps, the FortiGate could recover from a stable recovery point that is under control.

Related documents:

Technical Tip: Selecting an alternate firmware for the next reboot