I’ve written a lot about Hyper-V on this blog (some would say too much – I was recently accused of having lost all objectivity) but I’m going to carry on regardless. What I’ll try to do is steer clear of the arguments about how it competes with alternative technologies and stick to technical details. After all, this blog’s not really about news and comment – it’s supposed to be technical.

John Howard published a detailed blog post when Hyper-V RTMed but I’ve spent a fair amount of time recently clearing up confusion about the various versions of Hyper-V, so I’ll try and clarify things here:

• Windows Server 2008 (with Service Pack 1 – i.e. the version that was released to manufacturing on 4 February 2008 – build number 6001.18000.080118.1840) includes the beta for Hyper-V. After that, there were two public release candidates (RC0 and RC1) before the final product was released on 26 June 2006.
• Between the beta and the various RCs there were restrictions on the ability to upgrade virtual machines; but this did improve with later releases and I have successfully upgraded my release candidate VMs to RTM (depending on the version from which the upgrade is taking place, there may still be some limitations – see Microsoft knowledge base article 949222).
• The RTM version of Hyper-V can not be installed on pre-release versions of Windows Server 2008.
• John Howard has written a blog post explaining the process of updating the Windows Server 2008 RTM images to include the RTM version of Hyper-V.
• If you install a 32-bit version of Windows Server, there is no Hyper-V (it’s a 64-bit only product); however there is a 32-bit update for Hyper-V. Microsoft knowledge base article 950050 explains that the 32-bit update contains the Hyper-V Manager console and the Virtual Machine Connection tool for x86-based systems.
• There are also versions of Windows Server 2008 available without Hyper-V, sold for a $28 discount. I believe that the $28 is a token value to appeal those who would cry foul if Microsoft bundled “free” middleware with their operating system. These do not contain any components from the Hyper-V role (which may be stating the obvious but you never know…). Functionally, there is no difference between the Windows Server 2008 SKUs with and without Hyper-V up to the point when the Hyper-V role is enabled (at which point the hypervisor slides under the existing OS and it becomes the parent partition).
• Microsoft has also announced a product called Microsoft Hyper-V Server (which should not be confused with the Hyper-V role in Windows Server 2008) – this will be a standalone hypervisor product and will retail for $28 but Microsoft has not yet disclosed full details of Hyper-V Server.
• Other Hyper-V related updates/downloads include:
  • Language Pack (Microsoft knowledge base article 951636).
  • Management tools for Windows Vista SP1 (Microsoft knowledge base article 952627).
  • Release Notes.

Hopefully, that explains the various software products that include the Hyper-V branding or are in some way related to Hyper-V.