Other supported upgrade paths
FortiGate-6000 and 7000 for FortiOS 6.0.6 also supports the following upgrade paths for a standalone FortiGate-6000 or a FortiGate-6000 HA cluster with uninterruptible-upgrade
disabled:
- 5.6.7 build 4214 or 4261
->
6.0.4 build 8405->
6.0.6 build 6392 - 5.6.11 build 4279
->
6.0.6 build 6392 -
6.0.4 build 6145 or 8405
->
6.0.6 build 6392
Perform the upgrade during a maintenance window, because traffic will be interrupted during the upgrade.
After the firmware upgrade, you should manually delete IPsec VPN load balancing flow rules, see Manually deleting IPsec VPN load balancing flow rules.