You are working as an administrator of example.

Do the following steps as:

1.vi /etc/named.conf

zone “example.com” IN {

type master;

file “example.com.zone”;

};

/etc/named.conf file is used to register the zone as well as specify the global option for DNS. There are two types of zone, i. Master, which contains the original data. ii. Slave, backup of master. Here master zone is configured and file name is specified “example.com.zone”, which should be created in /var/named/chroot/var/named/

2.vi /var/named/chroot/var/named/example.com.zone

$TTL 345345

@ IN SOA @ webmaster.example.com.(

101;Serial Number

1H;Refresh Time

1M;Retry Time

1W;Expire Time

1D;Minimum Time to Live

)

@ IN NS 192.100.0.X

www 0 IN A 192.100.0.1

www 0 IN A 192.100.0.2

www 0 IN A 192.100.0.3

www 0 IN A 192.100.0.4

www 0 IN A 192.100.0.5

mail IN A 192.100.0.6

mail1 IN A 192.100.0.7

mail2 IN A 192.100.0.8

@ IN MX 5 mail.example.com.

@ IN MX 8 mail1.example.com.

@ IN MX 10 mail2.example.com.

3.service named start

4.rndc reload

5.chkconfig named on

Zone file should create on /var/named/chroot/var/named. Default Directory Path is specified on /var/named.conf.

$TTLTime To Live, How much seconds cache server stores the information about DNS. And Five Parameters specified Serial Number used by slave to synchronize with master server. Refresh and Retry Time used by slave server. NS is the Name (DNS)server where lookup the domain. A (Associated IP) for particular host. DNS has mechanism to load balance the request from clients. You can verify using hostwww.example.com command. MX resource records are used to define mail handler or exchanger for the domain. MX record must pass the positive integer value. This integer value is used by remote Mail Transport Agent (MTA) to determine, which host has delivery priority for the zone. The Lowest integer value will get the priority.