How to verify OSPF Configuration:

Show IP route command

Show IP ospf command

Show ip ospf database command

Show ip ospf interface command

Show ip ospf neighbour command

Show ip protocols command

Debugging ospf

  The Show IP route command:

R1#sho ip route

     10.0.0.0/30 is subnetted, 3 subnets

C       10.1.1.0 is directly connected, Serial0/0/1

O       10.10.10.0 [110/128] via 10.20.20.2, 00:05:14, Serial0/0/0

                   [110/128] via 10.1.1.2, 00:05:14, Serial0/0/1

C       10.20.20.0 is directly connected, Serial0/0/0

        172.16.0.0/24 is subnetted, 1 subnets

O       172.16.10.0 [110/65] via 10.1.1.2, 00:05:14, Serial0/0/1

O       192.168.1.0/24 [110/65] via 10.20.20.2, 00:07:38, Serial0/0/0

C    192.168.20.0/24 is directly connected, FastEthernet0/0

R1#

Using the the above command displays all routes on the network, with the O representing the OSPF internal routes. The Cs are directly connected networks. It also found the dual route to the 10.10.10.0 network.

 

 

 

 

The Show ip ospf neighbour command:

R1#show ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface

192.168.1.1       0   FULL/  -        00:00:33    10.20.20.2      Serial0/0/0

172.16.10.1       0   FULL/  -        00:00:32    10.1.1.2        Serial0/0/1

R1#

The above command displays the summary of ospf information regarding and the adjacency state. This command is very useful on a production network.

 

 The Show IP protocols command:

This command display the following information

 

R1#show ip protocols

Routing Protocol is "ospf 1"

  Outgoing update filter list for all interfaces is not set

  Incoming update filter list for all interfaces is not set

Router ID 192.168.20.1

Number of areas in this router is 1. 1 normal 0 stub 0 nssa

Maximum path: 4

  Routing for Networks:

    192.168.20.0 0.0.0.255 area 0

    10.20.20.0 0.0.0.3 area 0

    10.1.1.0 0.0.0.3 area 0

   Routing Information Sources: 

    Gateway         Distance      Last Update

    172.16.10.1          110      00:14:00

    192.168.1.1          110      00:14:40

    192.168.20.1         110      00:14:00

  Distance: (default is 110)

R1#

This command is used to verify the type of protocols running on your router and network. The display above shows the OSPF process ID, OSPF router ID, type of OSPF area, networks and areas configured for OSPF neighboring router’s ID etc…etc.

 

  The Debugging OSPF Command:

Among information provided by this command is the :

i.   Debug ip ospf packet: this command displays hello packets being sent and received on your router

ii.  Debug ip ospf hello: this command displays hello packets being sent and received on your router. It also displays more information than the debug ospf packet

iii. The debug ip ospf adj: shows DR and DBR elections on a broadcast and non-broadcast multi-access (NBMA) network.