DNS Server - Setting-up for Debian and Ubuntu(Ubuntu 8.04 LTS Ubuntu 10.04 LTS)

This is a step by step tutorial on how to install and configure DNS server for your LAN using bind9. The DNS server will provide caching and name resolution as well as reverse name resolution for your local network. In this tutorial, we will use the domain "exx007.com" and this will be the domain of your local network. The domain "debian.lan is not accessible from the internet; its private ip address is "192.168.100.1".

Installing bind9 and dns utilities

I assume that you already have a working Debian or Ubuntu installation and running Virtual Server's. Lets install the bind9 package and dns utilities from Debian repository.

apt-get install bind9 dnsutils (For Linux Desktop Edition Only)

Configure your Linux system

Add this information to your /etc/hostname

echo "ns1.exx007.com" > /etc/hostname

Edit your /etc/hosts

127.0.0.1       localhost.localdomain   localhost

192.168.100.1   ns1.exx007.com ns1

# The following lines are desirable for IPv6 capable hosts

::1     ip6-localhost ip6-loopback

fe00::0 ip6-localnet

ff00::0 ip6-mcastprefix

ff02::1 ip6-allnodes

ff02::2 ip6-allrouters

ff02::3 ip6-allhosts

Edit your /etc/resolv.conf

vi /etc/resolv.conf

and add this information.

search exx007.local

nameserver 192.168.100.1

nameserver xxx.xxx.xxx.xxx

nameserver xxx.xxx.xxx.xxx

This is where Linux looks to find out how it should perform DNS lookups.

Lets create a zone

The zone files (or database files) are the heart of your BIND system. This is where all the information is stored on what hostname goes with what ip address.
Before we create a zone file, lets edit first the local configuration file/etc/bind/named.conf.local.

vi /etc/bind/named.conf.local

and the zone file data.

//

// Do any local configuration here

//

// Consider adding the 1918 zones here, if they are not used in your

// organization

//include "/etc/bind/zones.rfc1918";

zone "debian.lan" {

        type master;

        file "db.exx007.com";

};

zone "100.168.192.in-addr.arpa" {

        type master;

        file "db.192.168.100";

};

Lets start creating a zone file in /var/cache/bind/ directory. Create a file called db.exx007.com

vi /var/cache/bind/db.exx007.com

And add the following entry

$TTL 604800

@ IN SOA ns1.exx007.com. admin.exx007.com. (

                2008080101      ;serial

                04800           ;refresh

                86400           ;retry        

                2419200         ;expire

                604800          ;negative cache TTL

                )

@       IN      NS      ns1.exx007.com.

@       IN      A       192.168.100.1

@       IN      MX      10      ns1.exx007.com.

main    IN      A       192.168.100.1

www     IN      CNAME   ns1

ubuntu  IN      A       192.168.100.2

Lets create the reverse DNS zone file called db.192.168.100

vi /var/cache/bind/db.192.168.100

and the the following entry.

$TTL 604800

@ IN SOA ns1.exx007.com. admin.exx007.com. (

                2008080101      ;serial

                604800          ;refresh

                86400           ;retry

                2419200         ;expire

                604800          ;negative cache TTL

                )

@       IN      NS      ns1.exx007.com.

@       IN      A       192.168.100.1

1       IN      PTR     ns1.exx007.com.

2       IN      PTR     ubuntu.exx007.com.

The zone files are created, you can check your zone file configurations using these utilities:

named-checkzone convergence.com /etc/bind/zones/db.convergence.com

Lets edit the file /etc/bind/named.conf.options

vi /etc/bind/named.conf.options

forwarders {

                202.78.97.41;

                202.78.97.3;

        };

Uncomment the line forwarders and add your ISP's DNS server.

dig exx007.com

Lets restart our DNS server, and test using the tool dig.

/etc/init.d/bind9 restart
dig exx007.com

You should see the following message

; <<>> DiG 9.3.4 <<>> exx007.com

;; global options:  printcmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54950

;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; QUESTION SECTION:

;exx007.com.                    IN      A

;; ANSWER SECTION:

exx007.com.             64800   IN      A       192.168.100.1

;; AUTHORITY SECTION:

exx007.com.             64800   IN      NS      ns1.exx007.com.

;; ADDITIONAL SECTION:

ns1.exx007.com.         64800   IN      A       192.168.100.1

;; Query time: 1 msec

;; SERVER: 192.168.100.1#53(192.168.100.1)

;; WHEN: Tue Aug  5 09:33:40 2010

;; MSG SIZE  rcvd: 79

Test your reverse DNS

dig -x exx007.com

If you see this message, you have successfully installed the DNS server.

; <<>> DiG 9.3.4 <<>> -x exx007.com

;; global options:  printcmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 42510

;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:

;com.exx007.in-addr.arpa.       IN      PTR

;; AUTHORITY SECTION:

in-addr.arpa.          10800   IN      SOA     A.ROOT-SERVERS.NET. dns-ops.ARIN.NET. 2008080416 1800 900 691200 10800

;; Query time: 952 msec

;; SERVER: 192.168.100.1#53(192.168.100.1)

;; WHEN: Tue Aug  5 09:34:25 2010

;; MSG SIZE  rcvd: 108

You can also check your DNS configuration using nslookup and host command.

nslookup exx007.com
nslookup 192.168.100.1
host exx007.com
host 192.168.0.1

All computers in the LAN are going to use 192.168.100.1 as a nameserver, this can be set manually by setting statically:

vi /etc/resolv.conf

then put this information.

nameserver 192.168.100.1

Have fun!
Sources:
http://www.debian.org/doc/manuals/network-administrator/ch-bind.html
http://www.aboutdebian.com/dns.htm