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| 6.3 |  | OSPF Configuration and Verification |
| 6.3.1 |  | Configuring OSPF on routers within a single area |

In this section, the student will learn how to configure OSPF on routers within a single area.

To configure OSPF, enable OSPF on the router and configure the network addresses and area information for the router according to the following steps:

1. Enable OSPF on the router using the following command:

   Router(config)#router ospf process-id

The process ID is a process number on the local router. The process ID is used to identify multiple OSPF processes on the same router. The number can be any value between 1 and 65,535. The OSPF processes do not need to be started at one (1). Most network administrators keep the same process ID throughout the entire AS. It is possible to run multiple OSPF processes on the same router, but is not recommended because it creates multiple database instances that add extra overhead to the router.

2. Identify IP networks on the router, using the following command:

Router(config-router)#network address wildcard-mask area area-id

For each network, identify the area to which the network belongs. The network address value can be the network address, subnet, or the address of the interface. The router knows how to interpret the address by comparing the address to the wildcard mask. A wildcard mask is necessary because OSPF supports CIDR and VLSM, unlike RIP v1 and IGRP. The area argument is needed even when configuring OSPF in a single area. Again note that more than one IP network can belong to the same area.

| Web Links Configuring OSPF http://www.cisco.com/en/US/products/ sw/iosswrel/ps1828/products_configuration_ guide_chapter09186a00800ca56c.html