OSPF Configured, but No OSPF Routes Appear

Symptom

router ospf 100 exists on both routers, yet show ip route ospf is empty.

Layered workflow

1 — Is the link itself healthy?

R1# show ip interface brief
R1# ping <direct-neighbour-IP>

No direct IP reachability means OSPF is not the first problem.

2 — Is OSPF enabled on the intended interface?

R1# show ip ospf interface brief

3 — Did a neighbour form?

R1# show ip ospf neighbor

No neighbour: compare area, subnet, timers, network type and authentication where configured.

4 — Only now inspect learned routes

R1# show ip route ospf
R1# show ip ospf database

Key lesson

A missing route can be the final symptom of an earlier adjacency failure. Troubleshoot the dependency chain, not the last symptom only.