The Default Route Is a Fact, Not a UI Guess
A topology view should consume routing state rather than infer a gateway from labels or layout.
routing
Exit Node or Subnet Router? I Choose Based on Which Traffic Must Move
Both features route packets through another tailnet device, but they solve different problems.
One Hostname, Some Public Paths, Some Private Paths: Make the Boundary Obvious
Path-based access control is safest when protected and public branches cannot accidentally fall through.
Routing Calls Across Two PBXs Without Turning Kamailio into a PBX
A two-PBX lab clarified the boundary between SIP routing at the proxy and dialplan or application behavior inside the PBX.
My First OSPF Lab: Watching Routes Appear Instead of Typing Them
OSPF became useful when I compared it directly with the static routes I had been maintaining by hand and watched neighbors and learned routes change with the topology.
How I Use a Tailscale Subnet Router to Reach Devices That Cannot Run Tailscale
The tailnet can reach printers, embedded devices and LAN-only services without installing a Tailscale client on every endpoint.
Linux Routing Tables: The Moment `ip route` Replaced Guessing
Once I started reading Linux routes as prefix decisions instead of interface settings, multi-interface hosts and lab gateways became much easier to debug.
Static Routing in a Three-Router Lab
A three-router topology is enough to show the most important routing lesson: reachability is directional, and the return path matters just as much as the forward path.
Router-on-a-Stick Was My First Clean Inter-VLAN Routing Lab
One router interface, an 802.1Q trunk and a few subinterfaces were enough to connect separate VLANs without hiding what was happening at Layer 2 and Layer 3.