I have an ASP.Net MVC site that has a subdomain for each customer e.g. customer1.site.com, customer2.site.com, etc.
Login works fine from customer1.site.com/login and customer2.site.com/login using the standard ASP.Net FormsAuthentication.
How can I login from the parent domain (e.g. site.com/login) where the user specifies the subdomain name in a form field? I'd like the auth cookie to be stored against customer1.site.com or customer2.site.com so obviously need to redirect and repost the login form somehow.