Ubuntu dns server configuration

Ubuntu dns server configuration involves many files. I would like to remind you again, please make a backup for every files before you begin editing. Example below:

luzar@ubuntu:/etc/bind$ sudo cp named.conf.local named.conf.local.bak
luzar@ubuntu:/etc/bind$ sudo cp named.conf.options named.conf.options.bak

The first file we are going to edit is the named.conf.local file. Use your favorite editor to open named.conf.local file.

luzar@ubuntu:/etc/bind$ sudo vim /etc/bind/named.conf.local

Type the code below. Replace example.com. with your domain name.

zone "example.com" in {
allow-transfer { any; };
file "/etc/bind/db.example.com.";
type master;
};


// Set up reversed name resolution
zone "1.168.192.in-addr.arpa" {
type master;
file "/etc/bind/db.192";
};

Example of /etc/bind/db.example.com configuration.

;
; BIND data file for local loopback interface
;
$TTL  604800
@   IN  SOA  ubuntu.example.com.  root.example.com. (
           2008112202           ; Serial
               604800           ; Refresh
                86400           ; Retry
              2419200           ; Expire
                86400 )         ; Negative Cache TTL
;

example.com   IN MX   mail.example.com.
@       IN NS           ubuntu.example.com.
@       IN A            192.168.1.3
ubuntu  IN A            192.168.1.3
web     IN CNAME        ubuntu.example.com.

Example of /etc/bind/db.192 configuration.

;
; Reverse lookup DNS Zone file
;
$TTL    604800
@   IN   SOA   ubuntu.example.com.  root.example.com. (
             2008112302         ; Serial
                 604800         ; Refresh
                  86400         ; Retry
                2419200         ; Expire
                  86400 )       ; Negative Cache TTL
@       IN NS           ubuntu.
3       IN CNAME        ubuntu.example.com.

You have to set the ISP dns server ip address. Put it in /etc/bind/named.conf.options forwarders:

        // If your ISP provided one or more IP addresses for stable
        // nameservers, you probably want to use them as forwarders.
        // Uncomment the following block, and insert the addresses replacing
        // the all-0's placeholder.


        forwarders {
        123.123.0.123;
        123.123.1.1;
        };

Example of /etc/resolv.conf configuration:

search example.comnameserver 192.168.1.3

Example of /etc/hosts configuration:

127.0.0.1       localhost
192.168.1.3     ubuntu.example.com      ubuntu

# The following lines are desirable for IPv6 capable hosts

::1     ip6-localhost ip6-loopbackfe00
::0 ip6-localnetff00
::0 ip6-mcastprefixff02
::1 ip6-allnodesff02
::2 ip6-allroutersff02
::3 ip6-allhosts

Restart bind9 service with the command below:

luzar@ubuntu:~$ sudo /etc/init.d/bind9 restart
 * Stopping domain name service... bind      [ OK ]
 * Starting domain name service... bind      [ OK ]

luzar@ubuntu:~$ tail /var/log/messages

Testing dns with dig domain name command:

luzar@ubuntu:/etc/bind$ dig example.com

; <<>> DiG 9.4.2-P2 <<>> example.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34700
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1,
ADDITIONAL: 1

;; QUESTION SECTION:;example.com.             IN      A


;; ANSWER SECTION:
example.com.        604800  IN  A    192.168.1.3


;; AUTHORITY SECTION:
example.com.        604800  IN  NS   ubuntu.example.com.


;; ADDITIONAL SECTION:
ubuntu.example.com. 604800  IN  A    192.168.1.3


;; Query time: 0 msec
;; SERVER: 192.168.1.3#53(192.168.1.3)
;; WHEN: Sun Nov 23 04:23:18 2008
;; MSG SIZE  rcvd: 82


luzar@ubuntu:/etc/bind$

Testing with dig ip address:

luzar@ubuntu:/etc/bind$ dig -x 192.168.1.3


; <<>> DiG 9.4.2-P2 <<>> -x 192.168.1.3
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35746
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1,
ADDITIONAL: 0


;; QUESTION SECTION:
;3.1.168.192.in-addr.arpa.       IN  PTR


;; ANSWER SECTION:
3.1.168.192.in-addr.arpa. 604800 IN  CNAME  ubuntu.example.com.


;; AUTHORITY SECTION:
example.com.            86400   IN   SOA   ubuntu.example.com.
root.example.com. 2008112202 604800 86400 2419200 86400


;; Query time: 0 msec
;; SERVER: 192.168.1.3#53(192.168.1.3)
;; WHEN: Sun Nov 23 04:32:09 2008
;; MSG SIZE  rcvd: 115
luzar@ubuntu:/etc/bind$

If you have an error during configuration, please check error logs in:

• /var/log/daemon.log.


• /var/log/messages.

Here is an example of /var/log/daemon.log:

luzar@ubuntu:/etc/bind$ tail /var/log/daemon.log

Nov 24 10:23:05 ubuntu named[4554]: zone 28.172.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone 29.172.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone 30.172.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone 31.172.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone 168.192.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone 1.168.192.in-addr.arpa/IN:
 loaded serial 2008112302
Nov 24 10:23:05 ubuntu named[4554]: zone 255.in-addr.arpa/IN:
 loaded serial 1
Nov 24 10:23:05 ubuntu named[4554]: zone example.com/IN:
 loaded serial 2008112202
Nov 24 10:23:05 ubuntu named[4554]: zone localhost/IN:
 loaded serial 2
Nov 24 10:23:05 ubuntu named[4554]: running