#ospf

I Am a Router — And I Just Made My First Friend

A first-person journey through OSPF neighbor formation, from loneliness to full adjacency. I woke up alone. Someone had just configured OSPF on my interface — network 10.0.0.0 0.0.0.255 area 0 — and

OSPF: Why the "Shortest Path" Isn't Always the Best Path

This week, I was deep in a multi-area OSPF lab on Cisco NX-OS and stumbled onto a scenario that defies standard "Cost" logic. The lab setup: 4x Cisco N9K switches in different OSPF areas. ASBR R4: Injecting a default route (0.0.0.0/0), Type E1, Me...

Open Shortest Path First (ospf)

Comparing Two Powerful Routing Protocols: A Deep Dive

When it comes to building and managing networks, routing protocols are the unsung heroes that make sure data packets find their way from one device to another efficiently and reliably. Among the most widely used routing protocols in today’s networks ...

𝄜 OSPF vs. BGP for SD-WAN | Hub-and-Spoke vs. Mesh ⿻

When designing an SD-WAN underlay, choosing between OSPF and BGP depends on the architecture: Hub-and-Spoke: BGP is usually the better choice. Full Mesh: Neither is ideal, but BGP scales better than OSPF. Let’s break this down. 1. Hub-and-Spoke ...

BGP & OSPF Multi-Area Routing Lab: ISP Peering & Route Redistribution

Introduction This lab simulates an enterprise network peering with two ISP routers via BGP, while utilizing a multi-layered, multi-area OSPF topology for internal routing. The goal of this setup is to explore BGP peering, OSPF multi-area configuratio...