I've got a Watchguard on which i'd like to use the optional Internface. The main goal is to redirect all traffic going to a particular subnet (for example 192.168.x.y) for any protocols. I'm not to watchguard world so i'm not sure on how to do this. Searched in the docs but nothing explicite about this. What's the way to follow ? route, services ?
You didn't say which WG appliance you have, it can make a subtle difference, but here is the short of it.
Open the Policy Manager, select Network, Network Configuration:
Interfaces Tab, you have an OPTIONAL INTERFACE IP ADDRESS, enter the IP Range/subnet you want to use.
As an example, on the Trusted Interface you might have 192.168.3.2/24 and on the Optional you might have 192.168.8.2/24
Don't forget to ADD the additional PUBLIC IP (if you have them) to the External Interface Aliases section or you won't be able to use them.
When you want to direct traffic to an Optional Interface, really any interface, you just add the rule, select Incoming Tab, select FROM EXTERNAL to (ADD - NAT) then Public IP Address > Optional Network IP Address (something like 126.96.36.199 -> 192.168.8.30. This will map all RULE traffic (HTTP or what you pick) on external IP to internal IP.