Lab Objective:
The objective of this lab exercise is for you to learn and understand how to configure DNS on Cisco IOS devices.
Lab Purpose:
Configuring DNS on Cisco IOS devices is a fundamental skill. DNS provides hostnames to Layer 3 address resolution. DNS servers are typically used in large networks with many hosts and internetworking devices. As a Cisco engineer, as well as in the Cisco CCNA exam, you will be expected to know how to configure DNS on Cisco IOS devices.
Certification Level:
This lab is suitable for CCENT and CCNA certification exam preparation.
Lab Difficulty:
This lab has a difficulty rating of 3/10.
Readiness Assessment:
When you are ready for your certification exam, you should complete this lab in no more than 5 minutes.
IMPORTANT NOTE: The objective of this lab is to simply familiarize you with the steps required to configure a Cisco IOS device to communicate with a DNS server. Because there will be no real DNS server configured against which to perform testing, the sole objective of this lab is command familiarity.
Lab Topology:
Please use any single router or switch to complete this lab.
Task 1:
Configure a hostname on your router or switch.
Task 2:
Configure your router or switch as part of the howtonetwork.com domain. For name resolution, your device should forward traffic to DNS servers 172.16.1.254 or 172.17.1.254.
Configuration and Verification
Task 1:
For reference information on configuring hostnames, please refer to earlier labs.
Task 2:
R1#conf t Enter configuration commands, one per line. End with CTRL/Z. R1(config)#ip domain-name howtonetwork.com R1(config)#ip name-server 172.16.1.254 172.17.1.254 R1(config)#ip domain-lookup R1(config)#end R1#
NOTE: If an actual DNS server was available and was providing name resolution, you could ping or connect to devices based on their hostnames as illustrated below:
R1#ping R3 Translating “R3.howtonetwork.com”...domain server (172.16.1.254) [OK] Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.254.3, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 8/11/16 ms R1#telnet R3 Translating “R3”...domain server (172.16.1.254) [OK] Trying R3.howtonetwork.com (192.168.254.3)... Open User Access Verification Password: R3#