Chapter 4. Scalable EIGRP

This chapter covers the following topics:

Configuring EIGRP—This section describes the basic configuration commands necessary to support routing.
Verifying the EIGRP operation—This section describes show and debug commands that will help evaluate the status of EIGRP.
Troubleshooting EIGRP—This section describes the process of diagnosing and repairing EIGRP problems.

This chapter details steps to configure EIGRP for IP routing. This chapter assumes general knowledge of routing protocols and the terminology, concepts, and operation of EIGRP (from Chapter 3, "EIGRP Principles"). This chapter introduces EIGRP configuration commands by explaining the required commands and then discussing the optional configuration commands that you can use.

The purpose of the "Do I Know This Already?" quiz is to help you decide what parts of this chapter to use. If you already intend to read the entire chapter, you do not necessarily need to answer these questions now.

The 12-question quiz, derived from the major sections in the "Foundation Topics" portion of the chapter, helps you determine how to spend your limited study time.

Table 4-1 outlines the major topics discussed in this chapter and the "Do I Know This Already?" quiz questions that correspond to those topics.

Table 4-1. "Do I Know This Already?" Foundation Topics Section-to-Question Mapping
Foundation Topics Section	Questions Covered in This Section	Score
Configuring EIGRP	1–7
Verifying the EIGRP Operation	8–10
Troubleshooting EIGRP	11–12
Total Score

Caution

The goal of self-assessment is to gauge your mastery of the topics in this chapter. If you do not know the answer to a question or are only partially sure of the answer, you should mark the question wrong for purposes of the self-assessment. Giving yourself credit for an answer you correctly guessed skews your results and might provide you with a false sense of security.


1.	What command starts the EIGRP routing process? router eigrp router eigrp autonomous-system-number ip routing eigrp ip eigrp routing
2.	What happens if no network command is configured? The EIGRP process is not activated on any interface. The EIGRP defaults to all interfaces. The EIGRP process can receive, but cannot send, updates. The router prompts you for the networks.
3.	What happens immediately after the network command is configured? Updates are sent. The routing table is created. Hellos are sent on appropriate interfaces. Networks are advertised.
4.	Where in the EIGRP network is it possible to summarize IP addresses? At a classful network boundary At the ASBR At the ABR At an interface
5.	Where is the command ip summary-address eigrp autonomous-system-number address mask configured? At the routing process At the interface After the network command At the EXEC command prompt

6.	What command is used to change the hello timer? eigrp hello-interval seconds hello interval seconds ip hello-interval eigrp autonomous-system-number seconds ip eigrp hello timer seconds
7.	Which of the following commands will show the hold time? show ip eigrp topology show ip eigrp traffic show ip eigrp holdtime show ip eigrp neighbors
8.	Which command is used to display the current status of EIGRP neighbors? show ip eigrp traffic show ip eigrp neighbors show ip eigrp adjacencies show ip eigrp database
9.	Which command is used to see the types of packets sent and received, as well as the statistics on routing decisions? show ip eigrp traffic show eigrp events debug ip eigrp packets debug ip eigrp traffic
10.	What types of information are shown by the show ip eigrp traffic command? Updates Hellos Queries and replies ACKs

11.	What is displayed in the command debug ip eigrp summary? A summary of EIGRP activity A summary of the contents of the neighbor database The process taken when a change is made in a summary route A summary of the topology database
12.	Which command could be used to show that EIGRP is able to contact neighbors? debug ip eigrp traffic debug ip eigrp packets debug ip eigrp events debug ip eigrp

The answers to the "Do I Know This Already?" quiz are found in Appendix A, "Answers to Chapter 'Do I Know This Already?' Quizzes and Q&A Sections." The suggested choices for your next step are as follows:

8 or less overall score—Read the entire chapter. This includes the "Foundation Topics" and "Foundation Summary" sections, the "Q&A" section, and the "Scenarios" section at the end of the chapter.
9-10 overall score—Begin with the "Foundation Summary" section, and then go to the "Q&A" section and the "Scenarios" at the end of the chapter. If you have trouble with these exercises, read the appropriate sections in "Foundation Topics."
11 or 12 overall score—If you want more review on these topics, skip to the "Foundation Summary" section, and then go to the "Q&A" and "Scenarios" sections at the end of the chapter. Otherwise, move to the next chapter.