Overview

Introduction

The Configure, Verify, and Troubleshoot Multi Area OSPFv2 for IPv4 module provides you with the instructions and Cisco hardware to develop your hands on skills in configuring the OSPF routing protocol in a multi area implementation using IPv4. This module includes the following exercises:

  • Configuring multi area OSPF
  • Examining the selection of DRs, BDRs
  • Configuring additional OSPF functions such as route cost

Exercise 1 - Configuring Multi Area OSPF

In this exercise, you will configure a multi area OSPF implementation. You’ll also learn how to verify your OSPF configuration using relevant show commands. ** In this exercise, you will configure OSPF area 1 on NYCORE1 and NYWAN1. This will make NYCORE1 an Area-Border Router or ABR as it will have interfaces in areas 0 and 1 and will be connecting area 1 to the backbone area 0.

Exercise 2 - Configuring Area 2

** In the previous exercise you configured OSPF area 1 which has NYWAN1 as an internal area router NYCORE1 as an ABR. You also saw that routes are injected into the routing tables as O or O IA depending on whether the route is sourced from an area other than the area the router is in.

Exercise 3 - DRs, BDRs and Route Cost

You have now built a relatively complex network with three areas, a number of subnets, a couple of ABRs, an internal router and a pair of backbone routers.

In this exercise we will look at what Designated Routers or DRs and Backup Designated Routers or BDRs are in the network and what bandwidth and reference costs are and how to use them.