Questions about setting up, configuring, and maintaining port forwarding configurations. Be sure the question actually relates to Ubuntu in some way.

Port Forwarding is a method of exposing certain computers/ports behind a NAT to the global Internet.

For example, a system administrator may want to access their server from anywhere in the world, but the server is behind a NAT. This administrator would set up port forwarding so that port 22 redirects to their server.

In the below example, port 22 is forwarded to the computer at IP Address 10.127.95.125. Anybody connecting to port 22 on the IP 47.92.91.41 will pass through the gateway and connect to the server.

[ Server - p22 ] ------- [ Gateway ] ---- <Internet> ---- [ Random Person]
 10.127.95.125    10.127.95.1     47.92.91.41

Port forwarding is a feature on most (if not all) consumer and enterprise-grade routers.