Recently I had to activate a second network interface on a Fedora 12 installation at work. The server has two interfaces (eth0 and eth1) but only one (eth0) was active and allowing connections from in-house only. The project wishes to provide a preview to the customer so I had to move the server to the DMZ. To avoid collisions between my work as system administrator and the development team I decided to activate the second interface(eth1) for the DMZ.
