Chapter 7. Domain Naming System

Understand How DNS And Name Resolution Works

Table of Contents

What is DNS?
What do we use DNS for?
Describe the name resolution process
The host file
DNS Name Server
NIS
So where to look up the host name?
Types of records in a DNS
Forward versus reverse name resolution
Describe round robin DNS servers
Troubleshooting your DNS client configuration
Is it a DNS problem?
Ensure names resolved from the correct place
Using NSLOOKUP
Using DIG, Why use DIG? How to use DIG? Examples

What is DNS?

DNS (Domain Name System) resolves the names of sites on the World Wide Web into IP addresses. Without a system like DNS we would not be able to type www.google.com into our browsers and expect to be taken to the Google Search engine's website. We would need to type http://216.239.57.99. BIND is a DNS server, it is the most widely used DNS server.