Step 6: Upgrade appliances
Upgrade all appliances that have not been upgraded in the above steps. This can be done in any order, and can be completed in parallel.
If you have deployed Forcepoint Email Security in cluster mode, release all appliances from the cluster before performing an upgrade. Upgrade or migrate each appliance as needed, then rebuild your cluster after the process is complete.
The Email MTA continues to function after the management server upgrade, but the logs are cached on the appliance until Forcepoint Email Security is upgraded as well. For best practice, redirect email traffic to another MTA as cached messages may be lost otherwise.
For more information, see the following: