Go2Linux shows you how to enable IP forwarding in Linux
If you want to use a Linux Operating System driven box, to act as a router or gateway, you need IP packets to pass through your Linux box. By default packets not directly addressed to a Linux powered PC will be discarded, so you need to enable IP Forwarding.How to enable IP forwarding in Linux
This can be done in different ways, and we'll check here some of the most common.