Hi, Ive set up LAN1 and WAN4 (as DMZ). Routing is working fine except the source ports are not being retained. I need the source port from a server in the DMZ to be the same when it is received on a server in the LAN. I.E. if the server sending the request is sending from port 1234 (for example) and it is sending to the destination server on Port 1234, I need the source port to be retained as it passes across the subnets/3900 router. At the moment it look like the source port is changing to a random port when going through. If read articles about this but with reference to F5, and they call this Preserve Port. I was wondering if I can achieve the same with the 3900? Thanks.