With all the hype surrounding Windows 8, a critical capability has been relegated to the background. It goes by the name Client Hyper-V and is one of the most important technologies of the new OS for desktop administrators.
Windows 8 Client Hyper-V brings Microsoft's virtualization hypervisor to desktop and laptop client PCs. Client hypervisors have been around for some time, but Client Hyper-V is unlike other desktop virtualization technology Microsoft has offered in the past. It's based on the Hyper-V hypervisor with Windows Server, and Windows 8 Client Hyper-V comes with many of the same goodies and requirements as the server version.
Client Hyper-V is made up of two primary applications: Hyper-V (the virtual machine manager that runs the VM software) and the Hyper-V Manager, where you create or remove virtual machines (VMs) and virtual hard drive (VHD) files. Once you've created a VM, you can install any OS you want, including Windows 3.1 through Windows 8, Linux, BSD and others.
Windows 8 Client Hyper-V requirements
Before working with Client Hyper-V, make sure your hardware is up to the task. You will need a 64-bit PC. Just like the server software on which it is based, Client Hyper-V only runs on 64-bit PCs that are running the 64-bit version of Windows 8 Pro (or Enterprise).
There are also some chipset requirements. Windows 8 Client Hyper-V requires modern Intel and AMD microprocessors that include Second Level Address Translation (SLAT) technologies. (That should be easy, because it's a feature of most existing generation microprocessors.) In addition, your PC must be configured with at least 4 GB of RAM. Naturally, more is always better with virtualization: Those looking for high-end performance and applications will want to load up on more RAM.
How to install Windows 8 Client Hyper-V
Hardware is only one part of the challenge with this client hypervisor. Client Hyper-V is not installed by default on Windows 8 Pro or Enterprise systems and is not available for any other OSes. To install it, you must find it first. It's in the well-hidden Windows Feature control panel, which you can access through the Windows 8 Start Search. Just search for Windows Features, then navigate to Settings, and then to the Turn Windows Features On or Off menu. Once there, installing Client Hyper-V takes little more than selecting a check box and rebooting the machine.
Once Client Hyper-V is installed on a Windows 8 Pro/Enterprise system, you'll see how similar it is to the server-based version of Hyper-V. If you know how to use Hyper-V in a virtual server environment, you will have no problem using Client Hyper-V for PC management.
Client Hyper-V features
Windows 8 Client Hyper-V brings a great deal of capabilities to the table and is a vast improvement over Microsoft's previous virtual desktop offering, Microsoft Virtual PC.
One nifty feature is the ability to control and access VMs that are located elsewhere on the network. That capability comes from the Hyper-V Manager, which not only connects to local VMs that were created using Client Hyper-V, but can also reach out to other servers and take control of remote Hyper-V virtual machines. They just need to authenticate first.
Windows 8 Client Hyper-V also brings enterprise capabilities such as the same storage migration capability that is included in Hyper-V in Windows Server 2012. That allows you to keep your VMs fairly independent of the underlying storage. You can move a VM's storage to and from one local drive to another, to a USB drive, or to a remote file share without needing to stop the machine.
Also, Client Hyper-V offers a new version of the file format VHD, called VHDX. VHDX offers much greater storage capacity than the older VHD format. It also provides data corruption protection during power failures and optimizes structural alignments of dynamic and differencing disks to prevent performance degradation on new, large-sector physical disks.
Client Hyper-V really shows it strengths when power users get a hold of it. It's an excellent environment for testing applications, creating digital sandboxes, testing application compatibility, creating virtual machines to run obsolete applications and so on. What's more, you can use Client Hyper-V as a mechanism to move physical clients into the virtual realm using tools such as Disk2VHD.
How Client Hyper-V differs from Hyper-V
You can compare Client Hyper-V directly to Server Hyper-V, but there are some critical differences. The Windows 8 version leaves out a few features built into the server version, including GPU virtualization (meaning no 3-D acceleration in Windows 8 VMs) and some exotic networking features such as Fibre Channel support.
Plus, if you used Windows XP Mode with Windows 7, that is not available in Client Hyper-V. Client Hyper-V can create a Windows XP virtual machine, but you will need a license to run Windows XP, whereas Windows XP Mode did not require any additional licenses.
Client Hyper-V brings virtualization to Windows 8 desktops, all without added expense or complexity. For many desktop administrators, the inclusion of Client Hyper-V may well be reason enough to move over to Windows 8 and Windows Server 2012.
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