How to Set Up A Linux Router
There are many ways in which you can set up a Linux router. It is hard to say which of the options is the best – it is up to you to decide. Here are the two ways to set up a Linux router:
1. Get a dedicated Linux distribution. Probably the easiest way to set up a Linux router is to use a dedicated Linux distribution, such as Linux LiveCD Router. As the name implies, Linux LiveCD Router is a Linux distribution with a router functionality. It is a Slackware-based live CD, which means that you don't have to install it to the hard drive - you can run it from a disk or a USB drive.
It is a small distribution but it has everything you need in order to set up a running Linux router. Unfortunately, the development of Linux LiveCD Router has been discontinued but the versions available online are usable.
2. Configure an existing Linux system to be used as a Linux router. If you don't like the idea to use a discontinued distro, you can use other Linux distros and with some adjustments you can make them fit for your purposes. Needless to say, this is the harder way. You can use almost any distro you like but it is best if you get a distro, such as Gentoo, where many of the functionalities you will need are already installed.
The procedure of setting a Linux router is pretty long and if you have a limited idea of networking, it might be a mission impossible for you. Still, if you are brave enough, this guide explains step by step what you need to do in order to turn your Gentoo into a Linux router.
If you favor other Linux distros, then you should check their site if there is a similar guide. Though most of the steps are similar for many Linux distributions, there are also differences that can turn everything upside down. One good guide, which is applicable to many Linux distributions, can be found here. Follow the instructions and with some luck, you will soon have your very own Linux router.