Setup and Configure DNS Server in Linux

by | Jan 14, 2015 | RHEL / CentOS

This guide will help you in setting up a DNS server for resolving IP address to domain names and vice-versa. We will be using “named (bind)” as its the DNS version for Linux. First we need to install named Packages.

 

# yum -y install bind*

 “*” is to say install all bind packages required

The make sure you have assigned a Static IP

# vi /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
HWADDR=00:0C:29:65:32:B2
ONBOOT=yes
BOOTPROTO=static
IPADDR=172.16.70.5
NETMASK=255.255.255.0
GATEWAY=172.16.70.1

Now assign a Fully Qualified Domain Name (FQDN)

# vi /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=dns-server.hm.local

Add host entry in hosts file

# vi /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
172.16.70.5 dns-server.hm.local

 Assign dns server IP as the nameserver

# vi /etc/resolv.conf
search hm.local
nameserver   172.16.70.5

Now we need to configure DNS config files
Edit named.conf as given below

# vi /etc/named.conf
listen-on port 53 { 172.16.70.5; };
# listen-on-v6 port 53 { ::1; };  [Disable ipv6 by putting "#"]
allow-query     { any; }; 

 * allow query from all clients in the network

Now edit named.rfc1912.zones file and add forward and reverse zone file entries

# vi /etc/named.rfc1912.zones
zone "hm.local" IN {                 ----> Your domain name
        type master;
        file "forward.zone";         -----> Forward zone file name
        allow-update { none; };
};
zone "70.16.172.in-addr.arpa" IN {      --------> Put in your IP Address subnet            
        type master;
        file "reverse.zone";            ---------> Reverse zone file name
        allow-update { none; };
};

Now create new forward and reverse zone files. Create a copy of the sample zone file installed with the package.

# cp /var/named/named.localhost /var/named/forward.zone
# cp /var/named/named.localhost /var/named/reverse.zone

Change group permissions of the files so that they are owned by “named”

# chgrp named /var/named/forward.zone
# chgrp named /var/named/reverse.zone

Now edit forward zone file and replace IP and hostname

# vi /var/named/forward.zone
$TTL 1D
@ IN SOA dns-server.hm.local. root.dns-server.hm.local. (      
                                        0       ; serial
                                        1D      ; refresh
                                        1H      ; retry
                                        1W      ; expire
                                        3H )    ; minimum
        IN NS   dns-server.hm.local.                      
dns-server        IN A    172.16.70.5
testhost1         IN A    172.16.70.6
testhost2         IN A    172.16.70.7

 Now edit reverse zone file and replace IP and hostname

# vi /var/named/reverse.zone
 $TTL 1D
@ IN SOA dns-server.hm.local. root.dns-server.hm.local. (
                                        0       ; serial
                                        1D      ; refresh
                                        1H      ; retry
                                        1W      ; expire
                                        3H )    ; minimum
        IN NS      dns-server.hm.local.
5       IN PTR     dns-server.hm.local.
6        IN PTR       testhost1.hm.local.
7        IN PTR       testhost2.hm.local.

 All config done and now its time to start DNS service.

# service named restart

 * Might take a while to startup 1st time
Output:

[root@dns-server ~]# service named start
Generating /etc/rndc.key:                                      [  OK  ]
Starting named:                                                [  OK  ]

Now to verify that all is working do a nslookup with IP and domain name, either should resolve vice-versa.
Output:

[root@dns-server ~]# nslookup dns-server.hm.local
Server: 172.16.70.5
Address: 172.16.70.5#53
 
Name: dns-server.hm.local
Address: 172.16.70.5
[root@dns-server ~]# nslookup 172.16.70.5
Server: 172.16.70.5
Address: 172.16.70.5#53
 
5.70.16.172.in-addr.arpa name = dns-server.hm.local.

If you encounter any errors during the process, let us know via Contact Us and will get it resolved promptly.

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