Installing BIND DNS server

Info

The steps below will configure a working bind DNS-server. The steps assume that you have a (fresh) CentOS 7 server running.

Install and configure bind (named)

• yum install bind bind-utils --> install bind and utils
• nano /etc/named.conf --> edit basic configuration

add above block "options": 
acl "dnsclients" { --> a logical name you will use later on
  localhost; --> the server itself
  x.x.x.x/x; --> your local subnet (example: 192.168.1.0/24 or 10.1.0.0/16)
  };

change: listen-on port 53 { 127.0.0.1; x.x.x.x; }; --> add the IP (x.x.x.x) of your server here
change (optional): # listen-on-v6 port 53 { ::1; }; --> disable IPv6 with a #

change: allow-query     { dnsclients; }; --> change to the acl you created earlier

add: include "/etc/named/named.conf.local"; to end of the file

• nano /etc/named/named.conf.local --> create the file that defines the zones

zone "testexample.com" { --> define the forward zone
  type master; --> type of the zone
  file "/etc/named/zones/db.testexample.com"; --> location of the forward zone file
};

zone "xx.xx.in-addr.arpa" { --> define the reverse zone (examples: 168.192.in-addr.arpa or 0.10.in-addr.arpa)
  type master;
  file "/etc/named/zones/db.xx.xx"; location of the reverse zone file (examples: db.192.168 or db.10.0)
};

Creating the forward zone-file

• nano /etc/named/zones/db.testexample.com --> create the forward zone

$TTL    604800
@   IN               SOA     ns1.testexample.com. admin.testexample.com. (
          1000     ; Serial
        604800     ; Refresh
         86400     ; Retry
       2419200     ; Expire
        604800 )   ; Negative Cache TTL
;
; NS-records
    IN               NS      ns1.testexample.com.
 
; A-records
ns1.testexample.com.          IN      A       x.x.x.x --> replace x.x.x.x with IP
<host1>.testexample.com.      IN      A       x.x.x.x --> replace x.x.x.x with IP
<host2>.testexample.com.      IN      A       x.x.x.x --> replace x.x.x.x with IP

Creating the reverse zone-file

• nano /etc/named/zones/db.xx.xx --> create the reverse zone

$TTL    604800
@       IN      SOA     ns1.testexample.com admin.testexample.com. (
                       20161012         ; Serial
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
;
 
; NS-records
        IN      NS      ns1.testexample.com.
 
; PTR Records
x.x     IN      PTR     <host1>.testexample.com. --> replace x.x with correct part of IP
x.x     IN      PTR     <host2>.testexample.com. --> replace x.x with correct part of IP

Check the configuration for errors

• named-checkconf --> if there's no output then the configuration is ok!
• named-checkzone testexample.com /etc/named/zones/db.testexample.com
• named-checkzone xx.xx.in-addr.arpa /etc/named/zones/db.xx.xx --> replace first "xx.xx" with right part of IP (example: 0.10.in-addr.arpa or 168.192.in-addr.arpa)

Start the bind server

• systemctl start named --> start the service
• systemctl enable named --> start the service at boot

Configure the firewall

• firewall-cmd --permanent --add-service=dns -->allow dns through firewall
• firewall-cmd --reload --> reload firewall with new configuration

Check if the DNS-server is functioning

• dig @x.x.x.x <host>.<domain>.<tld> --> replace x.x.x.x with the IP of your new bind DNS-server. It should respond.