• Enable Globally
    • ‘router ospf <process id>’
    • Network statements with IPs/wildcard masks
      • ‘network area <area #>
  • Enable Under Interface
    • ‘ip ospf <process id> area <area #>
    • If a manual router ID is needed, needs to be entered under the ‘router ospf <process id>’ configuration.
    • This enables OSPF for both primary and secondary IP addresses.
    • OSPF stays enabled even when IP address changes.
  • Verification basics:
    • ‘show ip ospf’
    • ‘show ip ospf int brief’
      • Quick way of showing which interfaces are enabled, which area each interface is in.
    • ‘show ip ospf neighbor
    • ‘debug ip ospf adjacency’
    • ‘show ip ospf database’

Below there are two routers running OSPF.

– Gig0/0 –
– L0 –
– L2 –

– Gig0/0 –
– L0 –
– L1 –

R1 OSPF Config:

R2 OSPF Config:

R1 Verification/Routing Table:

R2 Verification/Routing Table:

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