Those that remember Windows Server 2003 R2 may recall that it shipped on two disks: the first contained Windows Server 2003 with SP1 integrated; and the second contained the R2 features. When Windows Server 2003 SP2 shipped, it was equally applicable to Windows Server 2003 and to Windows Server 2003 R2. Simple.

With Windows Server 2008, it shipped with service pack 1 included, in line with it’s client operating system sibling – Windows Vista. When service pack 2 was released, it applied to both Windows Server 2008 and to Windows Vista. Still with me?

Today, one of my colleagues asked a question of me – what service pack level does Windows Server 2008 R2 sit at – SP1, SP2, or both (i.e. multiple versions). The answer is neither. Unlike Windows Server 2003 R2, which was kind of linked to Windows XP, but not really, Windows Server 2008 R2 and Windows 7 are very closely related. Windows Server 2008 R2 doesn’t actually display a service pack level in its system properties and I would expect the first service pack for Windows 7 to be equally applicable to Windows Server 2008 R2 (although I haven’t seen any information from Microsoft to confirm this). What’s not clear is whether the first service pack for Windows Server 2008 R2 and Windows 7 will also be service pack 3 for Windows Server 2008 and Vista? I suspect not and would expect Windows Server 2008 and Windows Server 2008 R2 to take divergent paths from a service pack perspective. Indeed, it could be argued that service packs are less relevant in these days of continuous updates. At the time of writing, the Windows service pack roadmap simply says that the “Next Update and Estimated Date of Availability” for Windows Server 2008 is “To be determined” and there is no mention of Windows 7 or Server 2008 R2.

So, three consecutive operating system releases with three different combinations of release naming and service pack application… not surprisingly resulting in a lot of confused people. For more information on the mess that is Microsoft approach to major releases, update releases, service packs and feature packs, check out the Windows Server product roadmap.