How to Block a Domain in Bind DNS Server on CentOS

Next edit the configuration file named.conf file for bind DNS and enter your IP address for that DNS server.

[root@ns1 ~]# vim/etc/named.conf
options {
        listen-on port 53 { 127.0.0.1  192.168.7.222  } 
        listen-on-v6 port 53 { ::1  } 
        directory       " /var/named"  
        dump-file       " /var/named/data/cache_dump.db"  
        statistics-file " /var/named/data/named_stats.txt"  
        memstatistics-file " /var/named/data/named_mem_stats.txt"  
        allow-query     { localhost  } 
        recursion yes 
        dnssec-enable yes 
        dnssec-validation yes 

        /* Path to ISC DLV key */
        bindkeys-file " /etc/named.iscdlv.key"  
        managed-keys-directory " /var/named/dynamic"  
} 

logging {
        channel default_debug {
                file " data/named.run"  
                severity dynamic 
        } 
} 
zone " ."  IN {
        type hint 
        file " named.ca"  
} 

include " /etc/named.rfc1912.zones"  
include " /etc/named.root.key"  

Start and enable the named service.

[root@ns1 ~]# service named start
Generating /etc/rndc.key:                                  [  OK  ]
Starting named:                                            [  OK  ]
[root@ns1 ~]# chkconfig named on

Next change the default DNS resolver to this newly installed DNS server’ s IP address in your network configuration file. Save and exit the file.

[root@ns1 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0
TYPE=Ethernet
UUID=36a6e616-74e3-4df5-ad16-ca3b691bc2d8
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=none
HWADDR=00:0C:29:F2:17:C6
IPADDR=192.168.7.222
PREFIX=24
GATEWAY=192.168.7.1
DNS1=192.168.7.222
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME=" System eth0" 

Restart the network service.

[root@ns1 ~]# service network restart
Shutting down interface eth0:  Device state: 3 (disconnected)
                                                           [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:  Active connection state: activated
Active connection path: /org/freedesktop/NetworkManager/ActiveConnection/1
                                                           [  OK  ]

Now the basic DNS server is up and ready. Set a domain to be blocked in the DNS. Open named.conf configuration file and make some changes as shown below in order to block a domain.

[root@ns1 ~]# vim /etc/named.conf
Create a zone as shown below to block facebook domain
zone " facebook.com"  {
type master 
file " block"  
} 

Create the forward zone file called “ block” in named.conf file. Enter the following contents in the file and save it.

[root@ns1 ~]# vim /var/named/block
$TTL 86400
@   IN  SOA     ns1.example.com. root.example.com. (
        2011071001   Serial
        3600         Refresh
        1800         Retry
        604800       Expire
        86400        Minimum TTL
)
@       IN  NS          ns1.example.com.
@       IN  A           192.168.7.222
*       IN  A           192.168.7.222

In that forward zone file enter any IP as fake or loop back IP so that the domain will be redirected to that responsive IP. The IP will be looped back and hence the domain will remain blocked. Restart the named service.

[root@ns1 ~]# service named restart
Stopping named:                                            [  OK  ]
Starting named:                                            [  OK  ]

Check with nslookup by running the following command. An output will be displayed like shown below if the domain is blocked.

[root@ns1 ~]# nslookup facebook.com
Server: 192.168.7.222
Address: 192.168.7.222#53

Name: facebook.com
Address: 192.168.7.222