This chapter covers the following topics:
Understanding DHCP—Describes the process of allocating IP addresses with DHCP.
DHCP Roles—Defines the server, relay, and client used by DHCP.
Troubleshooting DHCP—Lays out a seven-step process for troubleshooting DHCP.
This chapter is about using IPv4 DHCP (the Dynamic Host Control Protocol) with Cisco IOS. Cisco IOS devices may act as DHCP servers, relays, or clients, and this chapter deals with each case. This chapter also provides the configuration syntax with working examples.
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 11-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 13-1 outlines the major topics discussed in this chapter and the "Do I Know This Already?" quiz questions that correspond to those topics.
|Foundation Topics Section||Questions Covered in This Section||Score|
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 this question wrong for purposes of the self-assessment. Giving yourself credit for an answer you correctly guess skews your self-assessment results and might provide you with a false sense of security.
|1.||List the following actions in order: A-Acknowledgement, B-Discover, C-Offer, and D-Request.
|2.||DHCP is a descendant of what protocol?
|3.||Which of the following are roles a device can assume in DHCP?
|4.||Given the following configuration, users are not able to communicate through the router. What should be changed to fix the configuration?
interface f0/1 ip address 192.168.1.1 255.255.255.0 interface f0/0 ip address 172.16.15.1 255.255.255.0 ip dhcp pool exp_pool network 192.168.15.0 255.255.255.0
|5.||What is the default lease time for an IOS DHCP server?
|6.||How do you configure an IOS device as a DHCP client?
|7.||Which command is used to configure DHCP relay agents?
|8.||Which of the following ports are forwarded by UDP by default?
|9.||Which command is used to add a UDP port that should have broadcasts relayed through DHCP?
|10.||Which UDP broadcasts are automatically forwarded by an IOS DHCP relay?
|11.||What command generates the following output?
IP address Hardware address Lease expiration Type 172.16.1.11 00a0.9802.32de Feb 01 1998 12:00 AM Automatic
The answers to this 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: