Dns Configuration Documentation

DNS Server Configuration There are the files which must be configure if you want to make you LINUX operating system as Server. The three files are as follows: 1. /etc/resolv.conf 2. /etc/named.conf 3. /etc/hosts

/etc/resolv.conf: The initial structure of this file is as follows : ### BEGIN INFO # # ### END INFO # nameserver 127.0.0.1 search localhost When you want to configure your linux server then the basic change that you made on this file are as follows: ### BEGIN INFO # # ### END INFO # nameserver 172.31.1.30 nameserver 172.31.1.62 nameserver 172.17.14.47 nameserver 202.54.15.1 nameserver 172.16.1.1 search cc21447.iiita.ac.in

/etc/named.conf :The initial structure of this file is as follows: # The following zone definitions don't need any modification. The first one # is the definition of the root name servers. The second one defines # localhost while the third defines the reverse lookup for localhost. zone "." in { type hint; file "root.hint"; }; zone "localhost" in { type master; file "localhost.zone"; }; zone "0.0.127.in-addr.arpa" in { type master; file "127.0.0.zone"; }; # Include the meta include file generated by createNamedConfInclude. # includes all files as configured in NAMED_CONF_INCLUDE_FILES from # /etc/sysconfig/named

This

include "/etc/named.conf.include"; # # # #

You can insert further zone records for your own domains below or create single files in /etc/named.d/ and add the file names to NAMED_CONF_INCLUDE_FILES. See /usr/share/doc/packages/bind/README.SUSE for more details.

After the configureation of DNS we have new zone file which look like as # The following zone definitions don't need any modification. The first one # is the definition of the root name servers. The second one defines # localhost while the third defines the reverse lookup for localhost. zone "." in { type hint; file "root.hint"; }; zone "localhost" in { type master; file "localhost.zone"; }; zone "0.0.127.in-addr.arpa" in { type master; file "127.0.0.zone";

}; Zone “” in{ Type master; File “
This

include "/etc/named.conf.include"; # # # #

You can insert further zone records for your own domains below or create single files in /etc/named.d/ and add the file names to NAMED_CONF_INCLUDE_FILES. See /usr/share/doc/packages/bind/README.SUSE for more details.

Zone File for farward lookup file we follow the following structure $TTL 3D @

IN

SOA

ns1.cc21447.iiita.ac.in.

20080911

; Serial

3600

; Refresh, Seconds

3600

; Retry, Seconds

3600

; Expire, Seconds

3600 )

; Minimum, Seconds

NS

www

cc21447.iita.ac.in. localhost

MX A

; Inet Address of nameserver 1 mail

A

172.31.1.30

dns1

A

172.31.1.62

cc21447

A

172.17.14.47

cc21447

A

172.16.1.1

www mail

; Primary mail exchanger

127.0.0.1

dns0

ns1

root.cc21447.iiita.ac.in. (

CNAME cc21447 CNAME cc21447 CNAME cc21447

for the backward lookup or reverse lookup file we follow the following structure

$TTL 3D @

IN

SOA

www.cc21447.iiita.ac.in. 20080911

root.cc21447.iiita.ac.in. (

;Serial Number

8H

; Refresh, Seconds

2H

; Retry, Seconds

4W

; Expire, Seconds

1D )

; Minimum, seconds

NS

www

;Nameserver Address

62

PTR

dns1.iiita.ac.in.

30

PTR

dns0.iiita.ac.in.

47

PTR

cc21447.iiita.ac.in.

1

PTR

cc21447.iiita.ac.in.

1

PTR

ns1.cc21447.iiita.ac.in.

1

PTR

mail.cc21447.iiita.ac.in.

After doing all this setting we restart all the service.

Configure the /etc/hosts After configure the two above files we then configure one more file that is /etc/hosts at the very first stage the lookup of hosts file are as follows: # # hosts

This file describes a number of hostname-to-address

#

mappings for the TCP/IP subsystem. It is mostly

#

used at boot time, when no name servers are running.

#

On small systems, this file can be used instead of a

#

"named" name server.

# Syntax: # # IP-Address Full-Qualified-Hostname Short-Hostname # 127.0.0.1

localhost

# special IPv6 addresses ::1

localhost ipv6-localhost ipv6-loopback

when we configure our hosts file then it looks like as following : # # hosts

This file describes a number of hostname-to-address

#

mappings for the TCP/IP subsystem. It is mostly

#

used at boot time, when no name servers are running.

#

On small systems, this file can be used instead of a

#

"named" name server.

# Syntax: # # IP-Address Full-Qualified-Hostname Short-Hostname # 127.0.0.1

localhost

# special IPv6 addresses ::1

localhost ipv6-localhost ipv6-loopback

fe00::0

ipv6-localnet

ff00::0

ipv6-mcastprefix

ff02::1

ipv6-allnodes

ff02::2

ipv6-allrouters

ff02::3

ipv6-allhosts

#127.0.0.2

spine.spine.iiita.ac.in spine

172.31.1.31

dns0.iiita.ac.in

172.31.1.62

dns1.iiita.ac.in

#127.0.0.2

spine.spine.iiita.ac.in spine

172.16.1.1

cc21447 cc21447.iiita.ac.in

172.17.14.47

cc21447 cc21447.iita.ac.in

#127.0.0.2

cc21447.cc21447.iiita.ac.in cc21447

After configuring all these file yours DNS are ready to go . Good luck Amar Prakash Srivastava

MSCLIS Indian Institute of technology, Allahabad