Ben Armstrong, the Virtual Guy, just posted about the availability of a special version of Windows Server 2008 Release Candidate 1 that contains an updated version of Hyper-V, which is now a Beta.  The best news is this version is available for public download!

There's a small catch for testers though. It looks like the Windows Virtualization team releases new builds pretty rapidly and therefor is only testing new features on English non-localized version of the Enterprise version of Windows Server 2008. As you might already know Hyper-V will only be available in x86-64 versions of Windows Server 2008.

What's new

New features for Hyper-V in this first beta version in contrast with the previous Community Technology Preview (CTP) for Hyper-V are: (according to the Hyper-V Beta page)

• Quick migration. Enables movement of running virtual machines from one host to other host servers with minimal downtime.
• High Availability. Hyper-V beta now includes support for host-to-host connectivity and enables you to cluster all virtual machines running on a host.
• Server Core role. Hyper-V is now available as a role in a Server Core installation of Windows Server 2008.
• Integrated into Server Manager. Hyper-V is now integrated into Server Manager by default and customers can now enable the role within Server Manager.
• Live Backups with VSS. Hyper-V beta includes support for Volume Shadow Copy Services (VSS) to enable you to take Live Backups of running virtual machines in terms of snapshots.
• VHD tools. Hyper-V beta also includes support for VHD tools to enable compaction, expansion and inspection of VHDs created with Hyper-V.
• VM Manageability. Enables customers to easily import or export virtual machine settings to take backups of configurations and to be able to clone the virtual machine characteristics across different hosts.
• Linux integration components. Beta Linux integration components are now available for SUSE Linux Enterprise Server 10 SP1 x86 and x64 Editions. These integration components enable Xen-enabled Linux to take advantage of the VSP/VSC architecture and provide improved performance. Beta Linux Integration components are available for immediate download through http://connect.microsoft.com
• Improved performance. Hyper-V beta includes several fixes to improve performance. With the beta, all new Windows Server 2008 virtual machines will now automatically include the integration components.
• Improved access control with AzMan. Hyper-V beta now includes support for Authorization Manager (AzMan) to enable Role-Based Access Control models for better administration of the Hyper-V environment with increased security.
• Remote Management. Hyper-V beta now supports remote management and also provides a Hyper-V MMC only installation option for a separate management node.
• Increased Virtual SCSI support. The beta now includes support for up to four virtual SCSI controllers per virtual machine enabling broader disk support.
• Increased Memory Support. Hyper-V beta now supports up to 64GB of memory per virtual machine.
• Quick Reset. Hyper-V beta now provides administrators the option to quickly Reset Checkboxes and Delete saved credentials that are used to connect to virtual machines.

A lot of these features are features customers really needed according to the posts in the Microsoft TechNet forums on Windows Server 2008 Virtualization.

Buildnumber

The build number of this version of Release Candidate 1 is actually different than the buildnumber for the original Windows Server 2008 Release Candidate 1 released last week. What we're witnessing here is a new build of Windows Server 2008 in the Release Candidate branch. To clear this up here's a small table with the version numbers:

Overview

Along with the public download of Windows Server 2008 Release Candidate 1 Enterprise with Hyper-V Beta Microsoft also made a 17 page Word document available which contains an overview of the Hyper-V functionality. Be sure to download the document if you're interested in the following: (quoting from the document)

This white paper introduces Hyper-V as a key component of the Microsoft datacenter-to-desktop virtualization strategy. It shows how new and enhanced features in Hyper-V help relieve enterprise customer pain points in common scenarios: server consolidation, business continuity and disaster recovery management, testing and development, and the dynamic data center. It also highlights how these benefits scale to meet the unique needs of small businesses and branch offices.

Installation instructions

Natasha Mocke has written a very good how-to for installing the Windows Server Virtualization (WSV) role in Windows Server 2008 Release Candidate 0. This how-to is still 100% accurate for the first Windows Server 2008 Release Candidate 1. (with the exception the role in Server Manager is called Hyper-V instead of Windows Server Virtualization)

For the new Release Candidate 1 you don't have to locate and run the Windows6.0-KB939853-x64.msu and Windows6.0-KB939854-x64.msu packages from the Windows\WSV directory. Install this version of Windows Server 2008 will result in the Hyper-V role showing up in the Server Roles list within Server Manager.

Concluding

Microsoft is still behind on VMWare in the virtualization game, especially since the latter introduced version 3.5 build 64607 of its ESX product and version 2.5 build 64201 of its VirtualCenter product yesterday.

If you're only interested in Microsoft's product line up than you might consider this release an early Christmas present.

Further reading

Microsoft: Hyper-V Beta 1 available
Hyper-V beta released!
Download details: Windows Server 2008 Release Candidate 1 Enterprise with Hyper-V Beta
Download details: Windows Server 2008 Hyper-V Overview document
Virtual PC Guy's WebLog: Hyper-V Beta now available for download!
Microsoft Gets Hyper About Virtualization
Yes, Virginia, there is a Hyper-V beta
Hyper-V BETA (not CTP) is now available.
Hyper-V Beta: More Microsoft Gifting
Microsoft releases a beta for Hyper-V
Microsoft Unwraps Virtualization Surprise