How to configure Drupal to work with parked domains?
If you cannot log into your Drupal application using your parked domain, you should change the following line in the sites/default/settings.php file:
$cookie_domain = 'yourdomain.com';
$cookie_domain = $_SERVER['HTTP_HOST'];
This way Drupal will send the proper cookie information, matching the domain name you have used to access it.
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