Connect two operational units over LAN (SOPHOS UTM and SOPHOS XG)

Peter,

if you have a direct link, take an unused port on UTM and configure an IP which is not used in any network and put an IP on UTM interface port. On XG side, put another IP in the same network and create a new zone or use Internal zone. Make sure to create proper firewall on UTM and XG to allow traffic.

Regards

That's what I figure I would try.  Will it automatically route between the LAN's, assuming I have the appropriate firewall rules?

Of course. As soon you create a new interface, the routing table is updated with the interface network.

Of course if you need to advice other routes, you need to add static routes. For example if on UTM you have another network on another Interface (192.168.10.0/24), on XG you need to add a static routing saying "hey, in order to go to 192.168.10.0/24) you need this route (XG interface or UTM IP).

Regards

Perfect. I will do that for access to some of the other networks on the UTM.

I revised my diagram to show how I resolved this:

I cabled it a bit different, and had to add the appropriate static route in the UTM.  I also added the necessary firewall rules on the XG & UTM for the desired traffic.  Thank you iferrar for the suggestions.