HTTPS domain to HTTPS subdomain

Do you have hard-coded links somewhere pointing to https://mydomain.com/? Most end-users won't think to enter https in the protocol field in their browser so you might get by using a simpler http://mydomain.com/ to https://www.mydomain.com/ rule.

 

 

If they are though or if you have links to https://mydomain.com/ that you can't change, then I think you'll need an inexpensive ssl cert for your mydomain.com VIP in order to do this kind of redirection.