Page 106 - DCAP602_NETWORK_OPERATING_SYSTEMS_I

Network Operating Systems-I

notes 6.1.1 Configuring DNS Server

Domain Name System converts the name of a Web site for example (www.Ignou.ac.in) to an IP
address (220.227.168.115). This step is significant, because the IP address of a Web site’s server.
!

Caution The Web site’s name is not used in routing traffic over the Internet.
Dns Domains

Every person in the world has a first name and a last, or family, name. The same thing is true in
the DNS world: A family of Web sites can be loosely described a domain.

Example: The domain Ignou.ac.in has a number of children, such as www.Ignou.ac.in
and mail.Ignou.ac.in for the Web and mail servers, respectively.

BIND

BIND is an acronym for the Berkeley Internet Name Domain project, which is a group that
sustains the DNS-related software suite that runs under Linux. The most well known program in
BIND is named, the daemon that responds to DNS queries from remote machines.

DNS Clients

A DNS client doesn’t store DNS information; it has to refer to a DNS server to get it. The only
DNS configuration file for a DNS client is the /etc/resolv.conf file, which defines the IP address
of the DNS server it should use. You shouldn’t need to configure any other files. You’ll become
well acquainted with the /etc/resolv.conf file soon.

Task A family of Web sites can be loosely described a domain.

Authoritative DNS Servers

Authoritative servers offer the definitive information for your DNS domain, such as the names of
servers and Web sites in it. They are the last word in information related to your domain.

How DNS Servers find out your Site Information?

There are 13 root reliable DNS servers (super duper authorities) that all DNS servers query
first. These root servers know all the authoritative DNS servers for all the main domains - .com,
.net, and the rest. This layer of servers keeps track of all the DNS servers that Web site systems
administrators have assigned for their sub domains.

Example: When you register your domain my-site.com, you are in fact inserting a record
on the .com DNS servers that point to the authoritative DNS servers you assigned for your
domain. (More on how to register your site later.).

100 LoveLy professionaL university