In this article I will show you how to perform feature key renewals on a WatchGuard Firewall cluster.
Once you have baught for example a new 3-year License you will get a link to the renewal.

Once renewed get the new feature key and imprt it into the cluster.

Importing the new feature key

Start the Policy Manager and go to:
FireCluster > Confugure … > Members > highlight the Member > Edit > Feture Key > Import