PHP: SESSION lost on SUBDOMAIN

Question

I am trying to use session data on multiple subdomains:

• www.example.com
• my.example.com
• test.example.com
• whateversub.example.com

When I try to use session data from www.example.com to any subdomain, all the session information is not accessible.

• I am NOT using cookies. Just sessions.
• I have GoDaddy as web host.
• GoDaddy DOES allow to upload a custom php5.ini file.

Since I am a PHP beginner, please dumb down your response so I may understand it.

Here is an example:

File 1:

<?php
// FILE 1: www.example.com/index.php

session_start();
$_SESSION['status'] = "ON";
header( 'Location: http://sub.mywebsite/' );
?>

File 2:

<?php
// FILE 2: sub.example.com/index.php

session_start();
echo "Your session status is: ";
echo $_SESSION['status'];
?>

Answer 1

Be sure you set SESSIONID cookie on subdomain, too

ini_set('session.cookie_domain', '.my-domain.com');