In this video, we configure OSPF routing between a Core Switch and a Firewall and perform complete failover testing to verify redundancy, dynamic route exchange, and high availability. moreSo let's say I have just 2x Cat4k or 6k that I would like to enable OSPF between (one acts as Core switch where routing for access switches is done and other will be used for access and a bit of a backup, therefor won't be configured for HA), is it probably best to keep it simple and do ospfv2. I have been having trouble figuring out how to configure OSPF on the new core switches. They will uplink to a cisco switch which handles the main OSPF routing between multiple branch locations. All of my access layer switches are 6300's and they will connect to both 8360's kind of like this. OSPF uses link-state information to make routing decisions, making route calculations using the shortest-path-first (SPF) algorithm (also referred to as the Dijkstra algorithm).