====== Ubuntu - Bind - Configure Bind9 - Primary Nameserver ======

===== Forward Zone File =====

A DNS Zone resolves names to IP Addresses.

To add a DNS zone to BIND9, turning BIND9 into a Primary server, first edit **/etc/bind/named.conf.local**:

<file bash /etc/bind/named.conf.local>
zone "example.com" {
    type master;
    file "/etc/bind/db.example.com";
};
</file>

<WRAP info>
**NOTE:**  If bind will be receiving automatic updates to the file as with DDNS, then use **/var/lib/bind/db.example.com** rather than **/etc/bind/db.example.com** both here and in the copy command below.
</WRAP>

Use an existing zone file as a template to create the **/etc/bind/db.example.com** file:

<code bash>
sudo cp /etc/bind/db.local /etc/bind/db.example.com
</code>

Edit the new zone file **/etc/bind/db.example.com** as follows:

<file bash /etc/bind/db.example.com>
;
; BIND data file for example.com
;
$TTL    604800
@       IN      SOA     example.com. root.example.com. (
                     2014100501         ; Serial
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL

@       IN      NS      ns.example.com.
@       IN      A       192.168.1.10
@       IN      AAAA    ::1
ns      IN      A       192.168.1.10
</file>

<WRAP info>
**NOTE:** 

  * **Comment:**  Change this comment to refer to the domain that this file is for.
  * **Serial Number:** <WRAP important>
**must** be incremented every time changes are made to a zone file.

This Serial number can simply be any number, such as 1 or 2 or 3 etc.

The approach taken here is to use the last date this zone file was edited, in the format yyyymmddss (where ss is the change number for that day; 01 for 1st change, 02 for 2nd change, etc).
</WRAP>
  * **FQDNs:** <WRAP important>
Leave the additional **.** at the end of the FQDNs (example.com. and root.example.com.).
    * **root.example.com.** actually refers to an email address of root@example.com.  Change this as needed to a valid email address, but with a . instead of the usual @ symbol, and leaving a . at the end.
</WRAP>
  * Create an **A** record for the base domain, example.com.
  * Create an **A** record for the nameserver; in this example **ns.example.com**.
</WRAP>
 
<WRAP info>
**NOTE:**  Add any additional DNS records to the bottom of the zone file.

See [[[[Networking:DNS:Common Record Types|Common Record Types]] for details.
</WRAP>


Restart Bind for any changes to take effect:

<code bash>
sudo systemctl restart bind9.service
</code>

----

===== Reverse Zone File =====

A Reverse Zone needs to be added to allow DNS to resolve an address to a name.

Edit **/etc/bind/named.conf.local** and add the following:

<file bash /etc/bind/named.conf.local>
zone "1.168.192.in-addr.arpa" {
    type master;
    file "/etc/bind/db.192";
};
</file>

<WRAP info>
**NOTE:**  Replace 1.168.192 with the first three octets of whatever network you are using.

Also, name the zone file **/etc/bind/db.192** appropriately.  It should match the first octet of your network.

</WRAP>

Create the **/etc/bind/db.192** file:

<code bash>
sudo cp /etc/bind/db.127 /etc/bind/db.192
</code>

Edit **/etc/bind/db.192** changing the same options as **/etc/bind/db.example.com**:

<file bash /etc/bind/db.192>
;
; BIND reverse data file for local 192.168.1.XXX net
;
$TTL    604800
@       IN      SOA     ns.example.com. root.example.com. (
                     2014100501         ; Serial                              
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
;
@       IN      NS      ns.
10      IN      PTR     ns.example.com.
</file>

<WRAP important>
**IMPORTANT:**  The Serial Number in the Reverse zone needs to be incremented on each change as well.

For each **A** record you configure in **/etc/bind/db.example.com**, that is for a different address, you need to create a PTR record in **/etc/bind/db.192**.

</WRAP>

----

===== Restart Bind9 =====

<code bash>
sudo systemctl restart bind9.service
</code>

----