
Articles
Inter-VLAN routing: how traffic crosses between VLANs
Why two VLANs cannot reach each other at Layer 2, and how one Layer-3 interface per VLAN — a router subinterface or a switch SVI — routes traffic between them.

Why two VLANs cannot reach each other at Layer 2, and how one Layer-3 interface per VLAN — a router subinterface or a switch SVI — routes traffic between them.

What a routing table entry contains, how a device picks the longest matching prefix and its next hop, and what the default gateway and the default route actually are.

How a static route and a default route are written on Cisco IOS-XE, how the router chooses between routes, and when a manually configured route fails silently.