With the release of Windows 2012 and the support for Exchange 2013, what are the operating system requirements for the new email platform?
Exchange 2013 supports both Windows 2012 and 2008 R2 SP1 as the base operating system. The good thing is that you only need Windows 2012 Standard for any deployment of Exchange 2013 – be it the CAS, Mailbox or Mailbox server as part of a DAG. The standard edition of Windows 2012 includes the failover clustering feature which DAG requires. As I have written before, there is no enterprise version of Windows in 2012.
If you are using Windows 2008 R2 SP1 as the OS, you need standard edition of Windows for CAS, Hub, Edge, UM and Mailbox servers. If the mailbox server is part of a DAG, enterprise version of 2008 R2 is required.
Things are simple in Windows 2012 – all you need is a standard edition for any type of Exchange 2013 deployment. Since there are no enterprise edition in 2012, I am not sure whether the price for a standard edition is as expensive as an enterprise edition of 2008 R2 used to be.
The main difference between standard and enterprise edition of Windows 2012 is around the virtualization user rights.
In short, go with Windows 2012 and all you need is Standard edition for Exchange 2013.