Shared SSL is a means of securing the access to a site with SSL (Secure Sockets Layer) for site owners without having them purchase their own SSL certificate. Web sites that employ shared SSL are, in fact, using the certificate shared by another domain. The domain that shares its SSL certificate with others is called Master SSL Domain. Before your domains can use shared SSL, you need to configure the Master SSL Domain. It can be done on the server level, so that in theory any domain, including yours, can use shared SSL, and on the client level, so that only your domains can use shared SSL.
To configure the Master SSL Domain and enable shared SSL for your domains:
To disable shared SSL for your domains: