On 5/28/2014 12:00 PM, Michael Hennebry wrote: > I want the second computer to not have its own global IP address. > It will at least occasionally run Windows. > I'd prefer not to assume that Windows will > not try to fetch an IP address behind my back. what do you mean by 'global IP address' ? are you on a LAN behind some sort of firewall/gateway, or are these systems directly connected to the public internet ? To do what you describe, you'll need to configure the 2nd port on the primary system to be a private IP like 192.168.0.1, and implement IP Masquerade via iptables. You'll also want to configure a DHCP server on this second port so any clients connected to it will be offered IP's in that subnet. This will make that primary system act like a SOHO 'router' (I use quotes, because that sort of router is really a internet gateway appliance) note, btw, 'occasionally running windows' will be a huge pain. If occasional means a few times a month, nearly every time you boot up Windows, you'll be installing windows updates and rebooting. and flash and java and acrobat and all the rest of it..... -- john r pierce 37N 122W somewhere on the middle of the left coast