"Last time we left off after installing Webmin. Now it's time to configure the two network interfaces, then lock down security. Obviously, a firewall, like any network border device, must be highly secure.
"Since your firewall box has two network cards, you need to configure one with your WAN IP and one with a LAN IP. Additionally, it's a good idea to label each physical card so you know which one is which, and then use ifrename to ensure that the configurations stick to the correct cards..."