Posts Tagged ‘Hello packets’

OSPF Explained and Useful Troubleshooting Commands

Wednesday, January 4th, 2012

Open Shortest Path First (OSPF) is an open standard link-state routing protocol that supports multiple equal-cost routes to the same destination (four by default). OSPF constructs a shortest path tree and then updates the routing table with the best paths. In this blog I I will be explaining OSPF in the context of OSPF on Cisco routers, so I will be using Cisco IOS command syntax. For some of the commands I have included screenshots from a Cisco 2621XM [IOS 12.3(16a)] router. (more…)