There's been a lot of information around Windows Server 2008 Hyper-V this year, but one of the biggest outstanding questions regarded something called Microsoft Hyper-V Server 2008, a standalone version of the Hyper-V role in Windows Server 2008. This week, finally, those questions have been answered.

Monday, at a Microsoft Virtualization event in Bellevue, Washington, the software giant unveiled a few interesting virtualization news tidbits. For example, the company's System Center Virtual Machine Manager 2008 product, which can manage environments running on all of Microsoft's virtualization platforms, will ship within 30 days. The company also showed off some live migration features of Windows Server 2008 R2, due next year. Live migration will let customers move applications running in virtual environments from one server to another without disrupting users. VMWare already offers similar functionality.

System Center Virtual Machine Manager 2008 is the latest version of Microsoft's heterogeneous virtualization management server, and it can manage virtual machines hosted on Microsoft Virtual Server 2005, Windows Server 2008 Hyper-V, MHVS 2008, or VMWare. This tool is aimed at larger businesses that will host multiple environments virtually, Microsoft says.

Compared to its biggest competitor, Microsoft's tools are new and somewhat unproven, but they're also considerably less expensive than VMWare's offerings. Plus, Microsoft's management servers work fine with both physical and virtual environments, allowing corporations to mix and match between them as needed and use a single set of familiar tools. VMWare offers nothing like this, according to Microsoft.

The most exciting news from the event, however, was about Microsoft Hyper-V Server 2008. To differentiate this from the version of Hyper-V that ships in Windows Server 2008, I'll refer to the standalone version as Hyper-V Server 2008 from now on. (The Windows Server 2008 version is called Windows Server 2008 Hyper-V.)

As with System Center Virtual Machine Manager 2008, Hyper-V Server 2008 will ship within 30 days. Microsoft had previously revealed that they would sell this product for $28, but on Monday they announced that it would be given away for free and made available as a Web download. Like VMWare's ESX solution, Hyper-V Server 2008 is a "bare metal," hypervisor-based virtualization platform. The differences between the two are interesting, and which you'll use will depend on your needs.

First, Windows Server 2008 Hyper-V is Microsoft's most full-featured virtualization platform. With this product, Windows Server 2008 runs in the parent partition and provides unique capabilities around automated failover and high availability functionality. Larger enterprises will want to deploy Windows Server 2008 Datacenter in order to take advantage of that product's unlimited virtualization licensing as well.

With Hyper-V Server 2008, Microsoft's Hyper-V hypervisor is installed in the parent partition, and it provides just the bare essentials required for booting the system, providing hypervisor services, and exposing the management hooks necessary for Microsoft's System Center Virtual Machine Manager 2008. It does include drivers as well, but little else from Windows Server 2008. It's not Server Core. In fact, it's much less than that, though the environment looks very similar: At boot time, you'll be prompted from a command line interface to provide some basic configuration options such as the machine name and domain. (I'm trying to get a screenshot of this.) But actual management occurs from the free Hyper-V management console (on Vista or Windows Server 2008) or System Center Virtual Machine Manager 2008.

Microsoft says the performance characteristics of Windows Server 2008 Hyper-V and Hyper-V Server 2008 are identical. But this version of the product has a few differences. It's limited to four physical processors and 32 GB of RAM. There is no clustering support.

Because Hyper-V Server 2008 does not include Windows Server 2008, customers who choose to install this version of the hypervisor will typically run Windows Server 2000 or 2003, or SuSE Linux, in child partitions on the server. (You can run Windows Server 2008 in a child partition, but if you're going to do that, it makes more sense to use that as the parent partition and stick with Windows Server 2008 Hyper-V.) So it's a good solution only for those times when Windows Server 2008 is not needed. And if you still need to run NT 4.0 virtual machines, you'll have to stick with Virtual Server 2005 R2. Fortunately, all of these environments can be managed via a single tool, System Center Virtual Machine Manager 2008.

Microsoft has also opened up its certification program to its entire virtualization platform. There's a new certification specific to Hyper-V, and all of its server, desktop, and management standalone exams are being expanded with virtualization content.

Much of this article also appears in the September 9, 2008 issue of Windows IT Pro UPDATE. --Paul