It’s good practice to send WatchGuard Firebox traffic logs to a WatchGuard Dimension server so that you have a separate historic log of activity, as a Firebox won’t retain its logs over a power cycle. The WatchGuard Dimension server can be useful for troubleshooting, but also has a wealth of reports available as well.
To be able to send log traffic to the WatchGuard Dimension server it needs to be encrypted, so you need to supply enter an identical key on the Firebox and in the Dimension server.
If you have multiple Fireboxes you’ll need to know the existing encryption key so you can set it on the additional Fireboxes.
If you don’t know the encryption key, here is how to change it on the WatchGuard Dimension server (don’t forget to change it on existing Fireboxes).