Technical Tip: How to rollback firmware on FortiGate-6000 and 7000 series

[ESCHAN_FTNT]

Description

This article describes how to rollback firmware on the FortiGate-6000 and 7000 series.

FortiGate has two boot partitions on the flash memory to store the firmware images and configuration files.
During a firmware upgrade, the new FortiOS image is uploaded and saved in the secondary boot partition which on reboot is set as active partition. The previous firmware, saved in the primary boot partition is set as non-active partition.

Scope

For FortiGate-6000 and FortiGate-7000 series.

Solution

For the FortiGate-6000 and 7000 Series, the process is not straightforward to select alternate partitions to boot with.
The administrator will have to login to each individual FPC (Fortinet Processor Card) and MBD (Management Board) for 6000 Series or individual FPM (Fortinet Processing Module) and FIM (Fortinet Interface Modules) for 7000 Series and do it manually.
The situation becomes tricky when there are certain FPM/FPC modules that have a different active partition.

See the output below:

diagnose sys flash list
==========================================================================
Slot: 1  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    121098   48%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    121438   48%  Yes
3          EXDB-1.00000                                   14866900   1068832    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
Slot: 2  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    121094   48%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    121434   48%  Yes
3          EXDB-1.00000                                   14866900   1068832    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
Slot: 3  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    121150   48%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    121490   48%  Yes
3          EXDB-1.00000                                   14866900    985156    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
Slot: 4  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0335-200331                  253871    121438   48%  Yes
2          FG-6KF-6.00-FW-build0372-201013                  253871    121098   48%  No
3          EXDB-1.00000                                   14866900   1068832    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
Slot: 5  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    121096   48%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    121436   48%  Yes
3          EXDB-1.00000                                   14866900   1068828    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
Slot: 6  Module SN: FPC6KFTXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    121098   48%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    121438   48%  Yes
3          EXDB-1.00000                                   14866900   1068832    7%  No
Image build at Mar 31 2020 19:11:43 for b0335

==========================================================================
MBD SN: F6KF31TXXXXXXXXX
Partition  Image                                     TotalSize(KB)  Used(KB)  Use%  Active
1          FG-6KF-6.00-FW-build0372-201013                  253871    112666   44%  No
2          FG-6KF-6.00-FW-build0335-200331                  253871    113022   45%  Yes
3          EXDB-1.00000                                   14866900   1154260    8%  No
Image build at Mar 31 2020 19:11:43 for b0335

The majority of the active partitions are secondary partitions, except Slot #4.
As a result, the user will have to input the command 'execute-set-next-reboot primary' on all the blades (including MBD) while inputting the command 'execute-set-next-reboot secondary' on Slot #4, which can be confusing for some users, especially when dealing with 6500F series FortiGates that have 10 FPCs and one MBD.

There is one quick method to do this:

execute set-next-reboot rollback
==========================================================================
Slot: 1  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 1.

==========================================================================
Slot: 2  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 1.

==========================================================================
Slot: 3  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 1.

==========================================================================
Slot: 4  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 2.

==========================================================================
Slot: 5  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 1.

==========================================================================
Slot: 6  Module SN: FPC6KFTXXXXXXXXX
Default image is changed to image# 1.

==========================================================================
MBD SN: F6KF31TXXXXXXXXX
Default image is changed to image# 1.

The command will automatically set the default image to the current non-active partition, saving the effort to the administrator to do it manually on all the blades and also eliminating human error to boot the wrong partition.
Followed by a reboot, all slots in the chassis are now rollback to the previous firmware and configuration.