BGP

Border Gateway Protocol, the path-vector protocol that holds the internet together and increasingly runs inside enterprise data centers. Articles tagged BGP cover fundamentals, neighbor states, path attributes, best-path selection, traffic engineering, and Cisco IOS XE configuration.

40 posts

BGP

Troubleshooting BGP Route Advertisement Problems

The BGP session is Established but routes are missing. A missing prefix can be stopped at any of several pipeline stages, from injection to best path to output filtering. A methodical troubleshooting guide to BGP route advertisement.

Mar 28, 2026 4 min read

BGP

Troubleshooting BGP Neighbor Adjacency Issues

A BGP session that will not reach Established is the most common BGP issue. The FSM state tells you exactly where the problem is; the root cause inside each state can be one of many things. A systematic IOS XE methodology.

Mar 28, 2026 4 min read

BGP

BGP Design for Service Providers: Full Tables, Peering, and Transit

Service provider BGP operates at a scale that dwarfs enterprise: full tables, hundreds of peers, thousands of routers. An SP BGP design guide covering peering relationships, policy, iBGP scaling, and transit economics.

Mar 28, 2026 5 min read

BGP

BGP Design for Enterprise Networks: Dual-Homed and Multi-Homed

Enterprise BGP design comes down to how many ISPs, how many borders, full table or defaults, and active-active or active-standby. From single-homed to multi-homed with traffic engineering, and when you do not need BGP at all.

Mar 28, 2026 4 min read