Hack The Sec-Leading Resource Of Linux Tutorial: DNS

How to install and configure DNS server in ubuntu 14.04

<div dir="ltr" style="text-align: left;" trbidi="on">
<h1 style="clear: both; font-family: Trebuchet, 'Trebuchet MS', Arial, Verdana, sans-serif; font-size: 30px; height: auto; line-height: 31px; margin: 0px; padding: 0px; width: 614px;">
<span style="color: #990000; font-weight: normal;"><u>How to configure DNS server in ubuntu 14.04</u></span></h1>
<b style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;"><br /></b>
<b style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">DNS Server</b><span style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">. Domain Name System (</span><b style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">DNS</b><span style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">) is the name resolution protocol for TCP/IP networks, such as the Internet. Client computers query a </span><b style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">DNS server</b><span style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;"> to resolve memorable, alphanumeric </span><b style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;">DNS</b><span style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;"> names to the IP addresses that computers use to communicate with each other.<a href="https://help.ubuntu.com/14.04/serverguide/dns-configuration.html">More Info</a></span><br />
<strong style="background-color: white; display: block; font-family: Arial, sans-serif; margin: 0px 0px 3px; padding: 0px; text-decoration: none;"></strong><br />
<ul style="text-align: left;">
<li><strong style="background-color: white; display: block; font-family: Arial, sans-serif; margin: 0px 0px 3px; padding: 0px; text-decoration: none;"><a href="http://www.hackthesec.co.in/2016/01/how-to-setup-dns-bind-server-on.html" style="background-color: white; font-family: Arial, sans-serif; margin: 0px; padding: 0px; text-decoration: none;"></a><a href="http://www.hackthesec.co.in/2016/01/how-to-setup-dns-bind-server-on.html" style="margin: 0px; padding: 0px; text-decoration: none;"><strong style="display: inline !important; margin: 0px 0px 3px; padding: 0px;"><span style="color: red; font-size: large;">How to Setup <mark style="display: inline; margin: 0px; padding: 0px;">dns</mark> (Bind) Server on CentOS/RHEL 7/6/5</span></strong></a></strong></li>
</ul>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGq_yKmYg1KmOL7jL5bS-qzMryJn-Ffnn8Yt7rwudUwAxfYtYrUZE8H5ZLJp67qaI7bAQra2hiNRPTfYHspeVsjFtw9-sdcYTqgu6feCar75ltyxjPVIl4a31pYFFqVo9KV7VGjeh1lvUe/s1600/dns_bind_www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiGq_yKmYg1KmOL7jL5bS-qzMryJn-Ffnn8Yt7rwudUwAxfYtYrUZE8H5ZLJp67qaI7bAQra2hiNRPTfYHspeVsjFtw9-sdcYTqgu6feCar75ltyxjPVIl4a31pYFFqVo9KV7VGjeh1lvUe/s1600/dns_bind_www.hackthesec.co.in.jpg" /></a></div>
<span style="background-color: white; color: #222222; font-family: arial, sans-serif; font-size: 16px; line-height: 19.2000007629395px;"><br /></span>
<div style="background-color: white; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394; font-family: Roboto Slab;"><span style="font-size: 24px; line-height: 34px;"><b>DNS server installation</b></span></span></div>
<div style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394;">Step 1:</span><span style="color: #333333;"> </span>Update the repositories.</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; line-height: 1.3em;"># </span><span style="color: lime;"><span style="line-height: 15.6000003814697px;">sudo apt-get update</span></span></pre>
<div style="background-color: white; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394;">Step 2 : </span>Install bind9 using the below command.</div>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;"># </span><span style="color: lime;"><span style="line-height: 15.6000003814697px;">sudo apt-get install bind9</span></span><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;">
</span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
Now installation is over, please proceed with configuration.</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394; font-family: Roboto Slab;"><span style="font-size: 24px; line-height: 34px;"><b>Caching nameserver</b></span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;">Caching nameserver will remember all the DNS queries made and serves locally when the domain is queried second time. Default configuration will act as a caching nameserver, you just need is to add public DNS IPs in the configuration file.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;"><span style="color: #0b5394;">Step 3 : </span>Open <span style="color: red;">/etc/bind/named.conf.options</span> file and find forwarders column , uncomment and edit like the following.</span></span></div>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: Verdana, sans-serif;"><span style="line-height: 15.6000003814697px;">forwarders {
       8.8.8.8;
       8.8.4.4;
       };</span><span style="line-height: 1.3em;">
</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
Here 8.8.8.8 and 8.8.4.4 are google public DNS servers .<br /><span style="color: #0b5394;">Step 4 : </span>Now <b>start/restart</b> the service.</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;"># </span><span style="color: lime;"><span style="line-height: 15.6000003814697px;">sudo service bind9 restart</span></span><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;">
</span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394;">Step 5 : </span>Now test using dig command . open <span style="color: red;">/etc/resolv.conf</span> and edit nameserver ip to 127.0.0.1 or your serverIP.</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">nameserver 127.0.0.1</span></span><span style="color: white; font-family: Roboto Slab;"><span style="line-height: 1.3em;">
</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;">Now type the below command to see results.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">root@hackthesec:~$ dig www.hackthesec.co.in
................
;; Query time: 83 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
.................</span></span><span style="color: white; font-family: Roboto Slab;"><span style="font-size: 0.9em; line-height: 1.3em;">
</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
It took 83 msec for the first time . Now try the same command again.</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">root@hackthesec:~$ dig www.hackthesec.co.in
................
;; Query time: 5 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
.................</span></span><span style="color: white; font-family: Roboto Slab;"><span style="line-height: 1.3em;">
</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;">Now reduced to 5 msec . This time it serves from local.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394; font-family: Roboto Slab;"><span style="font-size: 24px; line-height: 34px;"><b>Primary master</b></span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
Primary master configuration is just like managing DNS records for particular domain locally ( Eg: hackthesec.co.in ).<br />Scenario details:<br /><b>Domain name : hackthesec.co.in<br />Server ip : 192.168.6.5<br />Server hostname : ns.hackthesec.co.in<br />Webserver ip : 192.168.6.10 ( www.hackthesec.co.in) .<br />We need to create 2 zone files , Forward zone and reverse zone.</b></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394; font-family: Roboto Slab;"><span style="font-size: 24px; line-height: 34px;"><b>Forward zone file</b></span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;"><span style="color: #0b5394;">Step 6 :</span><span style="color: #333333;"> </span>Create forward zone file <span style="color: red;">db.hackthesec.co.in</span> by copying db.local conf file.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;"># </span><span style="color: lime;"><span style="line-height: 15.6000003814697px;">sudo cp /etc/bind/db.local /etc/bind/db.hackthesec.co.in</span></span><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;">
</span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;"><span style="color: #0b5394;">Step 7 :</span><span style="color: #333333;"> </span>Now open<span style="color: red;"> /etc/bind/db.hackthese.co.in</span> and edit like below.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">; BIND data file for local loopback interface
;
$TTL    604800
@ IN SOA ns.hackthesec.co.in. root.ns.hackthesec.co.in. (
                              2         ; Serial
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
;
@       IN      NS      ns.hackthesec.co.in.
@       IN      A       192.168.6.5
@       IN      AAAA    ::1
ns      IN      A       192.168.6.5
www     IN  A 192.168.6.10</span></span><span style="color: white; font-family: Roboto Slab;"><span style="line-height: 1.3em;">

</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="color: #0b5394;">Step 11 :</span> Now restart the service.</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;"># </span><span style="color: lime;"><span style="line-height: 15.6000003814697px;">sudo service bind9 restart</span></span><span style="color: white; font-family: 'Roboto Slab'; line-height: 1.3em;">
</span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: Roboto Slab; font-size: large;"><span style="line-height: 28px;"><span style="color: #0b5394;">Step 12 : </span>Now test using nslookup or dig commands.</span></span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">root@hackthesec:~$ nslookup www.hackthesec.co.in
Server: 127.0.0.1
Address: 127.0.0.1#53
Name: </span></span><span style="color: white; line-height: 15.6000003814697px;">www.hackthesec.co.in</span><span style="color: white;"><span style="line-height: 15.6000003814697px;">
Address: 192.168.6.10</span></span><span style="color: white; font-family: Roboto Slab;"><span style="font-size: 0.9em; line-height: 1.3em;">
</span></span></pre>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
Now test reverse lookup</div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;">root@hackthesec:~$ nslookup 172.27.6.10
Server: 127.0.0.1
Address: 127.0.0.1#53
10.6.27.172.in-addr.arpa name = www.hackthesec.co.in.</span><span style="color: black; font-family: Roboto Slab;"><span style="font-size: 0.9em; line-height: 1.3em;">
</span></span></span></pre>
<pre style="background-attachment: scroll; background-clip: initial; background-color: #3c3c3c; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="line-height: 15.6000003814697px;"><a href="http://www.hackthesec.co.in/">Hack The Sec</a>
<a href="https://www.twitter.com/hackthesecurity">Hack The Sec Twitter</a>
<a href="https://www.facebook.com/htsecu">Hack The Sec Facebook</a></span></span></pre>
<div style="color: #333333; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px;">
<span style="color: white;"><span style="line-height: 15.6000003814697px;"><br /></span></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>

How to install and configure DNS server in ubuntu 14.04

How to configure DNS server in ubuntu 14.04 DNS Server . Domain Name System ( DNS ) is the name resolution protocol for TCP/IP networks,...

Install and Configure Caching-Only DNS Server in RHEL/CentOS 7

<div dir="ltr" style="text-align: left;" trbidi="on">
<span style="color: #990000; font-size: x-large;">Install and Configure Caching-Only DNS Server in RHEL/CentOS 7</span><br />
<span style="background-color: white; font-family: Verdana, sans-serif; line-height: 28.8px;">DNS servers comes in several types such as master, slave, forwarding and cache, to name a few examples, with cache-only DNS being the one that is easier to setup. Since DNS uses the UDP protocol, it improves the query time because it does not require an acknowledgement.</span><br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGmlA863bI-9bY9VrlFYVC-uB7nhDSRVe3oqRhIjT0ACX5k3aih65GwI1OegSFwsV_S82UZ8u84NNlNHPkgkfW_BTIbJ9xxAA2PCPELHRQNoIJwPBiCM7Jjj0SlsOzskdVbHOUOXHReufH/s1600/Setup-Cache-Only-DNS-in-CentOS-RHEL-7_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="306" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGmlA863bI-9bY9VrlFYVC-uB7nhDSRVe3oqRhIjT0ACX5k3aih65GwI1OegSFwsV_S82UZ8u84NNlNHPkgkfW_BTIbJ9xxAA2PCPELHRQNoIJwPBiCM7Jjj0SlsOzskdVbHOUOXHReufH/s640/Setup-Cache-Only-DNS-in-CentOS-RHEL-7_www.hackthesec.co.in.png" width="640" /></a></div>
<span style="background-color: white; font-family: "roboto condensed" , "arial" , sans-serif; font-size: 18px; line-height: 28.7999992370605px;"><br /></span>
<br />
<ul style="text-align: left;">
<li><span style="background-color: white; font-family: 'roboto condensed', arial, sans-serif; font-size: 18px; line-height: 28.8px;"><a href="http://www.hackthesec.co.in/2016/01/how-to-setup-dns-bind-server-on.html" target="_blank"><span style="color: red;">How to Setup DNS (Bind) Server on CentOS/RHEL 7/6/5</span></a></span></li>
</ul>
<span style="background-color: white; font-family: Verdana, sans-serif; line-height: 28.8px;">The cache-only DNS server is also known as resolver, which will query DNS records and fetch all the DNS details from other servers, and keep each query request in its cache for later use so that when we perform the same request in the future, it will serve from its cache, thus reducing the response time even more.</span><br />
<u><span style="font-family: Arial, Helvetica, sans-serif;"><span style="background-color: white; line-height: 28.8px;"><br /></span>
</span></u><br />
<div style="background-color: white; margin-bottom: 10px;">
<span style="color: #0b5394; font-family: Arial, Helvetica, sans-serif; font-size: small;"><span style="font-family: Arial, Helvetica, sans-serif; font-size: large; line-height: 18px;"><u>My Testing Environment</u></span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">DNS server  : dns.hackthesec.co.in (Red Hat Enterprise Linux 7.1)
Server IP Address : 192.168.1.17
Client   : node1.</span></span><span style="color: white; font-size: 12px; line-height: 15.6000003814697px;">hackthesec.co.in</span><span style="color: white; font-size: 12px; line-height: 15.6000003814697px;"> (CentOS 7.1)</span>
<span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">Client IP Address : 192.168.1.35</span></span></pre>
<div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="color: #0b5394; font-family: "arial" , "helvetica" , sans-serif;"><span style="line-height: 18px;">Step 1: Installing Cache-Only DNS Server in RHEL/CentOS 7</span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="line-height: 28.7999992370605px;"><span style="font-family: "arial" , "helvetica" , sans-serif;">1.The Cache-Only DNS server, can be installed via the bind package. If you don’t remember the package name, you can do a quick search for the package name using the command below.</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># yum search bind</span></span></pre>
<div>
<span style="color: white;"><span style="line-height: 15.6000003814697px;"><br /></span></span></div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">2.</span><span style="line-height: 28.7999992370605px;"> In the above result, you will see several packages. From those, we need to choose and install only</span><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">bind</span><span style="line-height: 28.7999992370605px;"> and </span><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">bind-utils</span><span style="line-height: 28.7999992370605px;"> packages using following yum command.</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># yum install bind bind-utils -y</span></span></pre>
<div>
<span style="color: white;"><span style="line-height: 15.6000003814697px;"><br /></span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="color: #0b5394; font-family: "arial" , "helvetica" , sans-serif; font-size: medium;"><span style="line-height: 18px;">Step 2: Configure Cache-Only DNS in RHEL/CentOS 7</span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">3.</span><span style="line-height: 28.7999992370605px;"> Once DNS packages are installed we can go ahead and configure DNS. Open and edit</span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><code style="background: none 0px 0px repeat scroll rgb(246, 246, 248); border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">/etc/named.conf</code><span style="line-height: 28.7999992370605px;"> using your preferred text editor. Make the changes suggested below (or you can use your settings as per your requirements).</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">listen-on port 53 { 127.0.0.1; any; };
allow-query     { localhost; any; };
allow-query-cache       { localhost; any; };</span></span></pre>
<div>
<div style="background-color: white; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin-bottom: 1em; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">These directives instruct the DNS server to listen on <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">UDP</span> port <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">53</span>, and to allow queries and caches responses from <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">localhost</span> and any other machine that reaches the server.</span></div>
<div style="background-color: white; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin-bottom: 1em; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">4.</span> It is important to note that the ownership of this file must be set to <code style="background-attachment: scroll; background-clip: initial; background-color: #f6f6f8; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">root:named</code> and also if<span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">SELinux</span> is enabled, after editing the configuration file we need to make sure that its context is set to<code style="background-attachment: scroll; background-clip: initial; background-color: #f6f6f8; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">named_conf_t</code> as shown in Fig. 4 (same thing for the auxiliary file <code style="background-attachment: scroll; background-clip: initial; background-color: #f6f6f8; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">/etc/named.rfc1912.zones</code>):</span></div>
</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># ls -lZ /etc/named.conf
# ls -lZ /etc/named.rfc1912.zones</span></span></pre>
</div>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="line-height: 28.7999992370605px;"><span style="font-family: "arial" , "helvetica" , sans-serif;">Otherwise, configure the SELinux context before proceeding:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># semanage fcontext -a -t named_conf_t /etc/named.conf
# semanage fcontext -a -t named_conf_t /etc/named.rfc1912.zones</span></span></pre>
</div>
<div>
<span style="color: white;"><span style="line-height: 15.6000003814697px;"><br /></span></span></div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">5.</span><span style="line-height: 28.7999992370605px;"> Additionally, we need to test the DNS configuration now for some syntax error before starting the bind service:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># named-checkconf /etc/named.conf</span></span></pre>
<div>
<span style="color: white;"><span style="line-height: 15.6000003814697px;"><br /></span></span></div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">6.</span><span style="line-height: 28.7999992370605px;"> After the syntax verification results seems perfect, restart the </span><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">named</span><span style="line-height: 28.7999992370605px;"> service to take new changes into effect and also make the service to auto start across system boots, and then check its status:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># systemctl restart named
# systemctl enable named
# systemctl status named</span></span></pre>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">7.</span><span style="line-height: 28.7999992370605px;"> Next, open the port 53 on the firewall.</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># firewall-cmd --add-port=53/udp
# firewall-cmd --add-port=53/udp --permanent</span></span></pre>
</div>
<div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="color: #0b5394; font-family: "arial" , "helvetica" , sans-serif; font-size: medium;"><span style="line-height: 18px;">Step 3: Chroot Cache-Only DNS Server in RHEL and CentOS 7</span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">8.</span><span style="line-height: 28.7999992370605px;"> If you wish to deploy the Cache-only DNS server within </span><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">chroot</span><span style="line-height: 28.7999992370605px;"> environment, you need to have the package </span><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">chroot</span><span style="line-height: 28.7999992370605px;"> installed on the system and no further configuration is needed as it by default hard-link to chroot.</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># yum install bind-chroot -y</span></span></pre>
</div>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="line-height: 28.7999992370605px;">Once </span><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">chroot</span><span style="line-height: 28.7999992370605px;"> package has been installed, you can restart named to take the new changes into effect:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># systemctl restart named</span></span></pre>
</div>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">9.</span><span style="line-height: 28.7999992370605px;"> Next, create a symbolic link (also named </span><code style="background-attachment: scroll; background-clip: initial; background-color: #f6f6f8; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">/etc/named.conf</code><span style="line-height: 28.7999992370605px;">) inside </span><code style="background-attachment: scroll; background-clip: initial; background-color: #f6f6f8; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">/var/named/chroot/etc/</code><span style="line-height: 28.7999992370605px;">:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"># ln -s /etc/named.conf /var/named/chroot/etc/named.conf</span></span></pre>
</div>
<div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="color: #0b5394; font-family: "arial" , "helvetica" , sans-serif; font-size: medium;"><span style="line-height: 18px;">Step 4: Configure DNS on Client Machine</span></span></div>
<div style="background-color: white; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">10.</span><span style="line-height: 28.7999992370605px;"> Add the DNS Cache servers </span><span style="border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">IP 192.168.0.18</span><span style="line-height: 28.7999992370605px;"> as resolver to the client machine. Edit</span><code style="background: none 0px 0px repeat scroll rgb(246, 246, 248); border-radius: 3px; border: 1px solid rgb(158, 158, 159); font-stretch: inherit; font-weight: 600; line-height: 1.6; margin: 0px; max-width: 100%; overflow: auto; padding: 2px; vertical-align: baseline; white-space: pre;">/etc/sysconfig/network-scripts/ifcfg-eth0</code><span style="line-height: 28.7999992370605px;"> as shown in the following figure:</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">DNS=192.168.1.17</span></span></pre>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">HWADDR=00:1A:4D:9A:F7:CE
TYPE=Ethernet
BOOTPROTO=static
IPADDR=192.168.1.35
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
NM_CONTROLLED=no
DEFROUTE=yes
PEERDNS=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFFROUTE=yes
IPV6_PEERDNS=yes
IPV6_PEEROUTER=yes
IPV6_FAILURE_FATAL=no
NAME=eth0
DNS=192.168.1.17
ONBOOT=yes</span></span></pre>
</div>
<div>
<div style="background-color: white; color: #333333; font-family: Verdana, Geneva, sans-serif; line-height: 1.5em; margin-bottom: 10px;">
<span style="color: #272727; font-family: "roboto condensed" , "arial" , sans-serif; line-height: 28.7999992370605px;">And </span><span style="border: 0px; font-family: "roboto condensed" , "arial" , sans-serif; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">/etc/resolv.conf</span><span style="color: #272727; font-family: "roboto condensed" , "arial" , sans-serif; line-height: 28.7999992370605px;"> as follows:</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">nameserver 192.168.1.17</span></span></pre>
</div>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin-bottom: 1em; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">11.</span> Finally it’s time to check our cache server. To do this, you can use dig utility or nslookup command.</span></div>
<div style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin-bottom: 1em; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif; line-height: 28.7999992370605px;">Choose any website and query it twice (we will use</span><span style="font-family: "arial" , "helvetica" , sans-serif; line-height: 28.7999992370605px;"> </span><span style="border: 0px; font-family: "arial" , "helvetica" , sans-serif; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; padding: 0px; vertical-align: baseline;">facebook.com</span><span style="font-family: "arial" , "helvetica" , sans-serif; line-height: 28.7999992370605px;"> </span><span style="font-family: "arial" , "helvetica" , sans-serif; line-height: 28.7999992370605px;">as an example). Note that with dig the second time the query is completed much faster because it is being served from the cache.</span></div>
</div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">root@hackthesec:/home/hackthesec# dig facebook.com

; <<>> DiG 9.9.5-9-Ubuntu <<>> facebook.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50459
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;facebook.com.   IN A

;; ANSWER SECTION:
facebook.com.  285 IN A 66.220.158.68

;; Query time: 65 msec
;; SERVER:192.168.1.17#53(</span></span><span style="color: white; font-size: 12px; line-height: 15.6000003814697px;">192.168.1.17</span><span style="color: white; font-size: 12px; line-height: 15.6000003814697px;">)</span>
<span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">;; WHEN: Mon Jan 25 16:59:32 IST 2016
;; MSG SIZE  rcvd: 57</span></span>
</pre>
</div>
<div>
<br /></div>
<div>
<div style="background-color: white; line-height: 1.5em; margin-bottom: 10px;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="line-height: 28.7999992370605px;">You can also use </span><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-stretch: inherit; line-height: 28.7999992370605px; margin: 0px; padding: 0px; vertical-align: baseline;">nslookup</span><span style="line-height: 28.7999992370605px;"> to verify that the DNS server is working as expected.</span></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;">[root@node1 ~]# nslookup facebook.com
Server:         192.168.1.17
Address:        192.168.1.17#53

Non-authoritative answer:
Name:  facebook.com
Address: 66.220.158.68</span></span></pre>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><span style="color: white;"><span style="font-size: 12px; line-height: 15.6000003814697px;"><pre style="background-attachment: scroll; background-clip: initial; background-image: none; background-origin: initial; background-position: 0px 0px; background-repeat: repeat; background-size: initial; border-radius: 4px; border: 1px solid rgb(229, 229, 229); font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"><a href="http://www.hackthesec.co.in/" target="_blank">http://www.hackthesec.co.in</a>
<a href="http://www.twitter.com/hackthesecurity" target="_blank">http://www.twitter.com/hackthesecurity</a>
<span style="color: #999999;"><a href="https://www.facebook.com/htsecu">https://www.facebook.com/htsecu</a></span></pre>
</span></span></pre>
</div>
<div>
<div style="background-color: white; color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 1.5em; margin-bottom: 10px;">
<br /></div>
</div>
</div>

Install and Configure Caching-Only DNS Server in RHEL/CentOS 7

Install and Configure Caching-Only DNS Server in RHEL/CentOS 7 DNS servers comes in several types such as master, slave, forwarding and ca...

How to Setup DNS (Bind) Server on CentOS/RHEL 7/6/5

<div dir="ltr" style="text-align: left;" trbidi="on">
<h2 class="title single-title title20" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 28px; line-height: 38px; margin: 0px 0px 5px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: red;">How to Setup DNS (Bind) Server on CentOS/RHEL 7/6/5</span></h2>
<div>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">The <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">DNS</span> (Domain Name System) is a distributed system, used for translate domain names to IP address and vice a versa.For example when we type domain name in browser url like “http://hackthesec.co.in”, Our computer sends a request to DNS and get an ip address of domain.</span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5cyk1AzeZppTEkL40wKG_nMdKeD_ueFZXRr5rSKPBuIbMjESBLrGzrUfbU_PRnFs-jhat6rHedD4UBOb3MncSn9UUjxRkdshQWbqPYaHrzyPCRSVYnCADzfQZAtAOqOdr8P2UC80PIIkK/s1600/dns_bind_www.hackthesec.co.in.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5cyk1AzeZppTEkL40wKG_nMdKeD_ueFZXRr5rSKPBuIbMjESBLrGzrUfbU_PRnFs-jhat6rHedD4UBOb3MncSn9UUjxRkdshQWbqPYaHrzyPCRSVYnCADzfQZAtAOqOdr8P2UC80PIIkK/s1600/dns_bind_www.hackthesec.co.in.jpg" /></a></div>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;"><br /></span></div>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">This article will help you to step by step setup dns server on CentOS and RedHat systems.</span></div>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="font-family: "arial" , "helvetica" , sans-serif;">Network Scenario:</span></span></div>
<ul style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin: 0px 0px 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<li style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; margin: 0px 0px 0px 30px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">DNS Server IP:</span> 192.168.0.200</span></li>
<li style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; margin: 0px 0px 0px 30px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">DNS Server Name:</span> ns1.hackthesec.co.in, ns2.hackthesec.co.in</span></li>
<li style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; margin: 0px 0px 0px 30px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Domain Name:</span> </span><span style="font-family: "arial" , "helvetica" , sans-serif;">hackthesec.co.in</span></li>
<li style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; margin: 0px 0px 0px 30px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="font-family: "arial" , "helvetica" , sans-serif;"><span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Domain IP to point:</span> 192.168.0.100</span></li>
</ul>
<h2 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 1 – Install Bind Packages</span></h2>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Bind packages are available under default yum repositories. To install packages simple execute below command.</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># yum install bind bind-chroot
</pre>
<h2 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 2 – Edit Main Configuration File</span></h2>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Default bind main configuration file is located under /etc directory. But using chroot environment this file is located at /var/named/chroot/etc directory. Now edit main configuration file and update content as below.</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># vim /var/named/chroot/etc/named.conf
</pre>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Content for the named.conf file</span></div>
<pre class="pretty" style="background: none 0px 0px repeat scroll rgb(240, 240, 240); border-left-color: rgb(116, 183, 63); border-left-width: 3px; border-radius: 5px; border-style: none none none solid; font-size: 0.9em; line-height: 1.5em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 8px 20px 8px 18px; vertical-align: baseline;">// /var/named/chroot/etc/named.conf
options {
        listen-on port 53 { 127.0.0.1; 192.168.0.0/24; 0.0.0.0/0; };
        listen-on-v6 port 53 { ::1; };
        directory       "/var/named";
        dump-file       "/var/named/data/cache_dump.db";
        statistics-file "/var/named/data/named_stats.txt";
        memstatistics-file "/var/named/data/named_mem_stats.txt";
        allow-query     { localhost; 192.168.0.0/24; 0.0.0.0/0; };
        recursion yes;

dnssec-enable yes;
        dnssec-validation yes;
        dnssec-lookaside auto;

/* Path to ISC DLV key */
        bindkeys-file "/etc/named.iscdlv.key";

managed-keys-directory "/var/named/dynamic";
};

logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};

zone "." IN {
        type hint;
        file "named.ca";
};

zone "<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">" IN {</span>
        type master;
        file "/var/named/<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.db";</span>
};

include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";
</pre>
<h2 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 3 – Create Zone File for Your Domain</span></h2>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">After creating bind main configuration file, create a zone file for you domain as per configuration, for example <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">hackthesec.co.in.db</span> in this article.</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># vim /var/named/chroot/var/named/hackthesec.co.in.db
</pre>
<div style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
Content for the zone file</div>
<pre class="pretty" style="background: none 0px 0px repeat scroll rgb(240, 240, 240); border-left-color: rgb(116, 183, 63); border-left-width: 3px; border-radius: 5px; border-style: none none none solid; font-size: 0.9em; line-height: 1.5em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 8px 20px 8px 18px; vertical-align: baseline;">; Zone file for <span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span>
$TTL 14400
@      86400    IN      SOA     ns1.<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">. webmaster.</span><span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">. (</span>
                3013040200      ; serial, todays date+todays
                86400           ; refresh, seconds
                7200            ; retry, seconds
                3600000         ; expire, seconds
                86400          ; minimum, seconds
      )
<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span>. 86400 IN NS ns1.<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.</span>
<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span>. 86400 IN NS ns2.<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.</span>
<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span>. IN A 192.168.0.100
<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span>. IN MX 0 mail.<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.</span>
mail      IN CNAME <span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.</span>
www      IN CNAME <span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">.</span></pre>
<div style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
If you are having more domain, its required to create zone files for each domain individually.</div>
<h2 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 4 – Add More Domains</span></h2>
<div style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
To add more domains in dns, create zone files individually for all domain as above. After that add any entry for all zones in named.conf like below. Change <span style="border-image-outset: initial; border-image-repeat: initial; border-image-slice: initial; border-image-source: initial; border-image-width: initial; border: 0px; font-size: inherit; font-weight: 700; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">hackthesec.co.in </span> with your domain name.</div>
<pre class="pretty" style="background: none 0px 0px repeat scroll rgb(240, 240, 240); border-left-color: rgb(116, 183, 63); border-left-width: 3px; border-radius: 5px; border-style: none none none solid; font-size: 0.9em; line-height: 1.5em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 8px 20px 8px 18px; vertical-align: baseline;">zone "<span style="font-size: 0.9em; line-height: 1.5em;">hackthesec.co.in</span><span style="font-size: 0.9em; line-height: 1.5em;">" IN {</span>
        type master;
        file "/var/named/hackthesec.co.in.db";
};
</pre>
<h2 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 5 – Start Bind Service</span></h2>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Start named (bind) service using following command.</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># service named restart
</pre>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Enable auto start on system boot.</span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># chkconfig named on
</pre>
<h5 class="heading1" style="background-color: white; border: 0px; font-family: 'Roboto Slab'; font-size: 24px; font-weight: bolder; line-height: 34px; margin: 45px 0px 12px; opacity: 1; outline: 0px; padding: 0px; transition: opacity 0.24s ease-in-out; vertical-align: baseline; visibility: visible;">
<span style="color: #0b5394;">Step 6 – Test Your DNS Setup</span></h5>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Send query to your dns server directly using below command.<br />Syntax: nslookup <domainname> <dns server name/ip></span></div>
<pre style="background: none 0px 0px repeat scroll rgb(60, 60, 60); border-radius: 4px; border: 1px solid rgb(229, 229, 229); color: white; font-size: 0.9em; line-height: 1.3em; margin-bottom: 20px; outline: 0px; overflow: auto; padding: 20px; vertical-align: baseline;"># <orange style="color: orange;">nslookup hackthesec.co.in <span style="color: white; font-size: 0.9em; line-height: 1.3em;">192.168.0.200</span><span style="font-size: 0.9em; line-height: 1.3em;"> </span></orange>

Server:         192.168.0.200
Address:        <span style="font-size: 0.9em; line-height: 1.3em;">192.168.0.200</span><span style="font-size: 0.9em; line-height: 1.3em;">#53</span>

Name:   hackthesec.co.in
Address: 192.168.0.100
</pre>
<div style="background-color: white; border: 0px; font-size: 16px; line-height: 28px; margin-bottom: 20px; outline: 0px; padding: 0px; vertical-align: baseline;">
<span style="font-family: "arial" , "helvetica" , sans-serif;">Above output is showing that dns server has successfully resolved domain hackthesec.co.in</span></div>
</div>
</div>

How to Setup DNS (Bind) Server on CentOS/RHEL 7/6/5

How to Setup DNS (Bind) Server on CentOS/RHEL 7/6/5 The DNS (Domain Name System) is a distributed system, used for translate domain n...