A Survey of the 7 Configuration Changes That Turn a Multi-homed Linux Host into a Switch/Router

This was written on March 1, 2026 What does it mean to turn a Linux system into networking infrastructure? I think it is incredibly cool that we can change a Linux system into a networking device. But have you ever wondered: What are we changing when we turn a Linux system into a router or switch? What are we changing if we make a raspberry pi into a WiFi access point? How significant is the system performance monitoring change? What are the gates we have to change to enable packet forwarding and processing? I’m going to start out with a narrative explanation of the changes that turn a Linux system into a WiFi access point and then I’ll show the commands for implementing it. I have a cognitive bias: I think of networking devices and computers as different things. This is because the command line experience on networking gear is different than what you experience on servers/hosts. On servers and workstations: you tend to focus a lot on objects on the file system. On networking gear,…