Upgrade Windows Azure web role to Server 2008 R2 to use IIS 7.5

I just launched my test website in Windows Azure this weekend with a single web role. I didn't see any options to specify what OS to use. It is currently using Server 200开发者_如何学JAVA8 (IIS 7). According to this article though, Server 2008 R2 web roles are available (IIS 7.5). I want to use some specific functionality of IIS 7.5 - how can I upgrade my web role to use Server 2008 R2?

Just specify osFamily="2" in ServiceConfiguration.cscfg.