Lab 20 – OSPF Configuration

  • Enable a loopback interface on all routers.
    • (config)#int loopback0
    • (config-if)#ip address [ip address] 255.255.255.255
  • Enable single area OSPF, exclude interfaces on edge router
    • (config)#route ospf 100
    • (config-router)#passive-interface [interface] – For segments that should not get ospf advertisement.
    • (config-router)#network 10.0.0.0 0.255.255.255 area 1
    • (config-router)#network 192.168.0.0 0.0.0.255 area 1
      • I forgot to add the loopback route
  • Show OSPF id
    • (config)#show ip protocols
  • Show router adjacencies
    • (config)#show ip ospf neighbors
  • Show all loopbacks are in the routing table
    • (config)#show ip route
  • Set reference bandwidth so that a 100 Gbps interface will have a cost of 1
    • (config-router)#auto-cost reference-bandwidth 100000
      • Had to look up in my notes for command
  • Verify the cost of the fastEthernet links
    • (config)#show ip ospf interface [interface]
      • Another lookup.
  • Edit the cost on the interfaces 
    • (config-if)#ip ospf cost [cost]