It is very simple to do the basic configure OSPF. The very first basic step is that, on a router, we have to enable OSPF as other routing protocols do (such as IGRP, rip, etc). A global configuration command, router OSPF PROCESS-ID is used for this purpose. The next step is to define all the advertising networks and the interfaces where we run OSPF are defined. For this purpose, there is a command used: WILDCARD_MASK AREA_ID. And it is from the OSPF Configuration mode.
To make a connection with the neighboring router, there is no need to become the OSPF process number be the same that are on that particular router. But on the other hand, the area ID should be unique to all the routes to say that it is a neighbor.

We can just go through some of the basic configurations of OSPF.

Configure OSPF Open Shortest Path First

The above figure shows an example of network topology. Where R1 and R2 are two routers. The very first step is to enable the OSPF on these two routers. The next step is the network definition. Here, we define the network that is advertised to the OSPF. This process is done by the use of some commands. We can define the network in R1 and R2 by using the commands shown below:

Defining network in R1:

Configure OSPF Open Shortest Path First




Defining network in R2:

Configure OSPF Open Shortest Path First




When these commands are processed, the routers R1 and R2 will be connected to the specific network. It may also include subnets. Another command, ” show IP OSPF neighbors” that can be used to check whether the routers become neighbors. This command can be run on any of the routers. In the above example, to check whether the R and R2 become neighbors by running this command on either R1 or R2.

Example: R2#show ip OSPF neighbors

Another command, ” show ip route ” can be used to check whether all the updations in the routing are changed. The OSPF routes are denoted by or marked with the O. To verify the updations are affected to the R2 router, then we can use the following command:

R2#show ip route

As we explained at the starting of this topic, it is very simple to do the basic configuration of OSPF, even the basic configuration is simple, the OSPF possesses many other advanced features. These features may lead the configuration to get complex.

Also, read…

Download How to Configure OSPF(Open Shortest Path First) in pdf – Click here