Learning path

Start here: how networks work

For: New to networking, or filling in the basics

From switches and IP addresses to a real router, then the two routing protocols everything else builds on.

1. Switching basics: layer 2, VLANs and IP addressingBeginner · 40 min

   How a switch learns MAC addresses and floods broadcasts, how IP subnets and default gateways decide where packets go, how VLANs split a switch into separate networks, and how trunks and a router connect them. Built on a real switch, three PCs and a VyOS router.

2. Linux Network ConnectivityBeginner · 80 min

   Find out why a Linux machine can't reach something, layer by layer: interfaces and addresses, routes and ip route get, ARP and the neighbour table, ping and traceroute, DNS, and listening sockets — with real output from a three-host lab.

3. Setting up VyOS with NATBeginner · 45 min

   A VyOS router with a NAT interface for a private LAN and a public interface for a routed public subnet: plain routing, source NAT, port forwarding and the forward firewall that NAT isn't. Every output comes from a real VyOS lab.

4. OSPF FundamentalsBeginner · 70 min

   The link-state IGP that runs inside most networks: neighbour adjacencies, LSA flooding, SPF, costs, DR/BDR, areas and LSA types, a hands-on FRR lab, and how OSPF underpins BGP.

5. BGP FundamentalsIntermediate · 75 min

   How the Border Gateway Protocol glues the internet together: autonomous systems, sessions, path attributes, best-path selection, iBGP scaling and a hands-on eBGP lab with real FRR configuration.

6. Building a network lab on an Apple Silicon MacBeginner · 45 min

   Run real network labs on an M-series Mac: native FRR and Linux containers, x86-only images through Rosetta, and full x86 VyOS VMs under QEMU in Docker, with the pitfalls that stop most people and a starter lab that mixes all three.