Please help with basic multisite subdomain setup

Using WordPress Multisite I have created http://books.ivoronline.com/ but when i use this link i get error This webpage is not available ERR_NAME_NOT_RESOLVED.

I have used cPanel to add
*.ivoronline.com
books.ivoronline.com
that point to
/public_html
and I have setup
wp-config.php and .htaccess as shown below.

WHAT AM I MISSING?

wp-config.php

define('WP_ALLOW_MULTISITE'  , true);
define('MULTISITE'           , true);
define('SUBDOMAIN_INSTALL'   , true);
define('DOMAIN_CURRENT_SITE' , 'ivoronline.com');
define('PATH_CURRENT_SITE'   , '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);
/* That's all, stop editing! Happy blogging. */

.htaccess

AllowOverride All
Order allow,deny
allow from all

# BEGIN WordPress
<IfModule mod_rewrite.c>

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^wp-admin$ wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^(wp-(content|admin|includes).*) $1 [L]
RewriteRule ^(.*\.php)$ $1 [L]
RewriteRule . index.php [L]

</IfModule>
# END WordPress