OSPF cheat sheet
A one-page OSPFv2 mental model, roles, packets and first checks.
Print at A4 / 100% scale, or save the PDF for your next study session. Free for personal study.
Scope: OSPFv2. Platform-specific commands and defaults can differ. This is an original study aid, not official certification material.
Protocol reference: RFC 2328 (OSPFv2). NSSA reference: RFC 3101.