The canonical hostname, using the full <em>subdomain.example.com</em> format. Leave off the http:// and the trailing slash and do not include any paths.<br />If this domain uses a custom http(s) port, you should specify it here, e.g.: <em>subdomain.example.com:1234</em><br />The hostname may contain only lowercase alphanumeric characters, dots, dashes, and a colon (if using alternative ports).