People, I am trying to get to grips with simple source routing in the advance routing how-to. I have a Linux box with two network cards Eth0 192.192.192.3 Eth1 10.10.10.1 With IP Forwarding switched on any machine on either network can ping any other machine. I can disable a user by adding a new route. What I want to do really is enable a machine to pass though the gateway. Do I need IP Forwarding on for this and if not what routes should I put in place. I guess I have missed something really simple here but I cant see it. Thanks Paul