We will use Perl script called “h2n” that creates the appropriate files for a DNS server. 

Download h2n Scripts---Click Here

Step 1:- Edit /etc/hosts file

• The new domain server will be on system 192.168.137.25 which is called SCAN.

• The following /etc/host file has been edit to contain all the DNS entries that are required:

192.168.137.25  scan.indiandba.com  scan

• Assume domain name is to be indiandba.com

• Assume network is 192.168.137

• Create a domain run directory to contain the Named services files called /var/named.

Step 2:- Create named directory and copy h2n script

$ mkdir -p /var/named
$ cp <from the ./h2n-2.56 directory>/h2n /var/named

Step 3:- Run the h2n script file as follows: 

$cd /var/named
$./h2n -d indiandba.com -n 192.168.137 -u oracle@indinadba.com

Step 4:- Download “named.root” file, rename the file to db.cache and copy to the /var/named directory.

Step 5:- Copy named.conf file to /etc directory

$ cp /var/named/named.conf /etc

Step 6:- Edit the file /etc/nsswitch.conf and add the entry dns to the host entry as follows: 

====================================================================

#

# /etc/nsswitch.files:
#
# An example file that could be copied over to /etc/nsswitch.conf; it
# does not use any naming service.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file has a "-" for nametoaddr_libs of "inet" transports.
passwd:     files
group:      files
hosts:      files dns
networks:   files
protocols:  files
:          :          :          :          :          :
:          :          :          :          :          :

=====================================================================

Step 7:- Create or edit a file called /etc/defaultdomain and add the single entry: 

$vi /etc/defaultdomain

indiandba.com

Step 8:- Execute the domainname command to set the domain as follows:

$domainname ‘cat /etc/defaultdomain’

Step 9:- Edit /etc/resolv.conf file

$vi /etc/resolv.conf
domain indiandba.com
nameserver      192.168.137.25

Step 10:- Start Named Services

$/usr/sbin/in.named &

Step 11:- To enabled the respository use

$svcs -a | grep dns
disabled         10:15:21 svc:/network/dns/server:default
disabled         10:15:22 svc:/network/dns/client:default

$svcadm enable /network/dns/server

$svcs -a | grep dns
online           10:15:21 svc:/network/dns/server:default
online           10:15:22 svc:/network/dns/client:default

Note:---- /network/dns/server must be online for DNS to run properly and initiate if the DNS server is rebooted.

Step 12:- Configurating Clients to use DNS To use DNS, clients need to modify the /etc/resolv.conf, and /etc/nsswitch.conf as above. The /etc/defaultdomain file must also be created and establsihed as above.

Reference: -

http://www.logiqwest.com/dataCenter/Demos/RunBooks/DNS/DNSsetup.html