OSPF network types are a small configuration detail with a big operational impact. They decide whether routers elect a DR/BDR, whether a Type-2 Network LSA appears, how neighbors form, and how easy the topology is to reason about during an outage. In many networks OSPF “just works” until a VLAN handoff, SVI, or routed link behaves differently on each side.
This guide focuses on the practical side: what the common OSPF network types mean, when to use point-to-point instead of broadcast, and how to troubleshoot neighbor states without jumping straight into random changes.