Finally, the long-awaited Windows hypervisor has been released with the
Windows Server 2008 RC0, which was earlier code named Longhorn. The Hypervisor
is still in its infancy, but that does not reflect upon the installation
process, which is as simple as adding a new Role to any Windows Server.
Once it is installed, you will love its usability and performance. Before we
go ahead, let's first understand in a nutshell what exactly is a hypervisor.
Understanding hypervisors
A hypervisor is a technique to run virtualization in full-virtualization
mode, which means a setup where the virtualization layer essentially runs on top
of the hardware and below the Operating System. You will know the difference by
comparing it with any traditional virtualization system, where the
virtualization layer runs on top of the host. The hypervisor runs directly on
top of the hardware, and uses the virtualization features of the underlying CPU,
eg. Intel's VT and AMD's Pacifica.
Direct Hit! |
Applies To: Sys admins, CIOs USP: Understand how to use MS WSV Primary Link: http://www.microsoft.com Google Keywords: Hypervisor, Longhorn, WSV |
As the virtualization layer sits directly on top of the hardware, it is very
thin and lightweight. It is also more resource conscious. Both of these features
make its performance much better as compared to traditional virtualization
techniques.
The other well known hypervisor is XEN from Citrix.
Prerequisites
To run Windows hypervisor, the list of prerequisites is not small. As we
said earlier the hardware should be running processors supporting virtualization
natively.
For our tests, we used a machine with an Intel Core2Duo Extreme 3.0 GHz
processor, which supports Intel VT. We used 2 GB RAM, as we had to dedicate some
of it to the guest machine and some to the host running Windows Server 2008.
Currently only the 64-bit version of Windows Server 2008 RC0 supports the
installation of hypervisor, so we had a copy of this as well.
Top two: Windows XP and 2003 running as virtual machines on Windows Server Virtualization. Bottom: Virtualization Management console to configure the VMs |
Installation
For installation of the Microsoft Hypervisor or the Windows Server
Virtualization role, you have to do some tweaking before you can install it
through the Server Management console. This is because WSV is not present in the
Add Role wizard of Server Management console, by default. To get this role
enabled, you have to first install two updates. No, you don't have to download
anything. These updates ship along with the Windows Server 2008 RC0 but have to
be installed separately.
To do so, first go to
MSU files. Install both of them, one by one. Once the installation is done, go
back to the Server Management console's Add role wizard and you will see a new
role called Windows Server Virtualization.
Now, go to Administrative tools and start Server Management console. Click on
the Roles option from the left of the window.
Now, if you can see Add role in the main window pane, then click on it. A
wizard will open. Select the penultimate option, which says Windows Server
Virtualization and follow the wizard till that gets installed.
Windows Hypervisor let's you create virtual machines through a simple wizard. It first asks you to give your VM a name |
You can install the OS for your VM from an optical disk, or from an ISO image |
You can define a new virtual HDD for your virtual machine, or boot from an existing one made from MS VPS or VS |
Using theHypervisor
To start working with the Windows Server Virtualization, go to the
Administrative tools again and click on the Windows Virtualization Manager. A
window will open.
From this window you can create, manage, modify and delete any guest OS on
the server.
To create a new guest OS you just have to click on Newon the right hand side
pane of the main window. It will open up a drop-down which will ask you whether
you want to create a Virtual machine, a Hard disk, or a Floppy disk.
Click on the Virtual machine option and a new wizard will pop up. Follow the
wizard as shown in the images and it will create a virtual machine for you.
Once you have created virtual machines, it's just a matter of turning them on
and using them from the Windows Virtualization Manager interface.
Interesting findings
One great thing about WSV is that it is backward compatible with .vhd files
created by VPC or MS Virtual Server. And it's just a matter of creating new
virtual machines with pre-existing hard-disk images, to use those old VHD's with
WSV. One problem we faced during this was that the graphical interface of Linux
is not very compatible with WSV, till now. We tried installing Fedora 7, Gentoo
and Mandriva on top of WSV, but none of them were able to start the graphical
interface while installing. But, as this is the first public Beta release of WSV,
it might be happening due to a bug, which will eventually be rectified.
Right now the technology looks very promising and we expect to see it
evolving as a robust hypervisor for Windows platform, in the coming future.