routing between two local ethernet connections

Question

I have added a second local network to my Sophos UTM 9, and the related firewall rules to allow traffic between them. 
 However, despite NOT having a masquerading rule, whenever I access sites between the two networks, the IP of the Sophos router is used. 
 I.e. I connect from 10.6.1.10 to 10.10.1.1, the machine at 10.10.1.1 logs the connection as coming from the 10.6.1.1 (Sophos router) ip! 
 I just want the router to route between the two subnets without changing anything (and I know each machine needs to know how to route back). 
 Thanks for your help!

kerobra_retired · Accepted Answer

Sounds like you are using transparent web protection for both subnets. 
 To have only the firewall rulesets involved between your local subnets you have to add both networks in the destination skip list. 
 If web traffic is proxied the destination always sees the UTMs IP as source, internal as external (you can not SNAT proxy traffic to an additional IP).