DNS server unique zone

The DNS [Domain Name System] is a key component of a network infrastructure. It allows you to use NAMES instead of IP addresses and technical garbage.

You can learn how it works through a simple Google request.

Here, I will present the installation of:

• DNS primary server (= DNS for domain smartcards.local) using BIND9
• Local domain (.local)

You can re-use all this content for a web-site or public domain. Just replace smartcards.local by mywebsite.com.

Setup

apt-get install bind9 dnsutils bind9-doc

Primary master

A DNS primary master is the main DNS for your local domain (ex: smartcards.local).

These are the steps to do:

• Set the external DNS to use by your server
  • File: /etc/bind/named.conf.options

• Declare the new domain to manage
  • File: /etc/bind/named.conf.local

• Create a dedicated configuration file for the new domain
  • New file: /etc/bind/smartcards.local

• Adjust the reverse zone
  • Rename and adjust file: /etc/bind/db.192

Set the external DNS

This is the list of DNS your server will use to populate its own cache.

The external DNS can either be your ISP's DNS or Google's servers.

!! Mind the order !! First DNS have a higher priority.

Edit configuration file:

vim /etc/bind/named.conf.options

Uncomment and adjust the file content

[...]
forwarders {
     # Local gateway or router
     172.16.50.1; 

     # Your ISP DNS IP’s 
     182.176.39.23;
     182.176.18.13;

     # Google's DNS
     8.8.8.8
     8.8.4.4
};
[...]

Declare the new domain

Edit configuration file:

vim /etc/bind/named.conf.local

Uncomment and adjust the file content

zone "smartcards.local" {
	type master;
        file "/etc/bind/smartcards.local";
};

Domain configuration file

Create the domain configuration file from a local template:

cp /etc/bind/db.local /etc/bind/smartcards.local

Edit configuration file:

vim /etc/bind/smartcards.local

Adjust the file content

;
; BIND data file for smartcards.local (you can use mywebsite.com)
;
$TTL    604800
@       IN      SOA     smartcards.local. root.smartcards.local. (
                   201406031132         ; Serial
                                        ; As the serial be changed everytime you edit this file
                                        ; it is recommended to use the pattern "yyyyMMddHHmm"
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
; 
; Primary DNS server declaration
; Each NS must point to an A record, not a CNAME. 
; This is where the Primary and Secondary DNS servers are defined
                 IN      NS      smartcard-gw.smartcards.local
smartcard-gw     IN      A       172.16.50.2

;
; -- alternative -- 
; To declare a server a specific domain only
;website.com      IN      NS      smartcard-gw.website.com
;website.com      IN      A       172.16.50.2

; Declare your servers and networks hosts 
smarcartd-prod-00 IN      A       172.16.50.10

; Create an alias to an existing record
;wwww             IN      CNAME   smartcard-gw

Reverse zone file

Edit configuration file:

vim /etc/bind/named.conf.local

Uncomment and adjust the file content