1) Restart httpd
2) Edit httpd.conf
Here is a great article on this topic http://www.careerride.com/PHP-sub-domains.aspx
You can read how to create subdomains using PHP step by step!
Dynamic subdomains like Google Blogger and Tumblr.com, I know most of the people are looking for better solution. Today I want to explain how to achieve this using .htaccess with PHP. I especially love to write .htaccess file, using this you can easily host multiple domains in single server. This dynamic subdomain system is the base for cloud services, soon I will come with new tutorial. I hope this post will solve your problem.
use this script to add new subdoamin in your cpanel account
subdomainform.php
<html>
<head>
<title>create a subdomain</title>
</head>
<body>
<form name="form1" method="post" action="addsubdomain.php">
<h1>create Sub Domains</h1>
Sub Domain Name : <input type="text" name="subdomain"><br />
<input type="submit" name="Submit" value="Submit">
</form>
</body>
</html>
==============================
addsubdomain.php
=============================
<?php
ini_set('display_errors', 1);
$host = "domainname.com"; // your domain name without the www
$port = 2082;
$path = "/frontend/x/subdomain/doadddomain.html?domain=".$_POST['subdomain']."&rootdomain=".$host; //or .dll, etc. for authnet, etc.
// these lines are changed
$cpaneluser = "username";
$cpanelpass = "pass";
$authstr = "$cpaneluser:$cpanelpass";
//****************************
// Setup the Auth String
$pass = base64_encode($authstr);
$fp = fsockopen($host, $port, $errno, $errstr, $timeout = 30);
if(!$fp){
//error tell us
echo "$errstr ($errno)n";
}else{
//send the server request
fputs($fp, "POST $path HTTP/1.1rn");
fputs($fp, "Host: $hostrn");
fputs($fp, "Authorization: Basic $pass rn");
fputs($fp, "Content-type: application/x-www-form-urlencodedrn");
fputs($fp, "Content-length: ".strlen($poststring)."rn");
fputs($fp, "Connection: closernrn");
fputs($fp, $poststring . "rnrn");
//*************************************
// Remove this to stop it from displaying the output fron the CPanel
//*************************************
//loop through the response from the server
/*
while(!feof($fp)) {
echo fgets($fp, 4096);
}
*/
while(!feof($fp)) { fgets($fp, 4096); }
//close fp - we are done with it
fclose($fp);
}