Azure session management

I have read the following from Azure in Action book: "开发者_如何学编程In Windows Azure, the state server, or out-of-process session state provider, isn’t supported"

Can anyone tell me why this is not supported. They do not explain in the book. I would have thought I could run the state server and all web roles would be able to use this to read session data. Thanks for replies

Windows Azure has the AppFabric Cache, which is well-suited for session storage. This went live about 2 weeks ago. You can see details in my StackOverflow answers here and here.

I can't give you an absolute answer on the lack of state server, other than the fact that until recently, Web Roles ran under Hosted Web Core instead of Full IIS and that might have had an impact on offering state server. Additionally, since all of your web role instances are equivalent, how would you specify which is the state server? And what happens if Windows Azure recycles that instance? I think this would be a big headache.

With the AppFabric Cache solution, this is cache-as-a-service, completely independent of your role instances, and managed for you. You simply get an endpoint, attach to the cache, and execute puts and gets on name/value pairs. Through the Azure portal, there's a Client Configuration button you click, and a magic chunk of xml gets generated for you - you place that in web.config, and you now have a custom session state provider that stores/retrieves session data to/from cache.

EDIT: On using SQL Azure for session state: SQL Azure doesn't have a SQL Agent, so you wouldn't have a background job periodically clearing the cache. There's an MSDN blog post showing how to get SQL Azure working as a session state provider (and using a worker role background process to perform session cleanup). However, I'd still recommend the AppFabric Cache solution.