Windows Server 2008 R2 provides the foundation for Win 7 virtualization

With the introduction of Windows Server 2008 R2, Hyper-V can now be moved from one host to another. This version of Windows Server is also the first version to be launched with Windows clients in 10 years. As a result, the Windows Server 2008 R2 contains a number of new features that can work better with Windows 7 implementations.

Windows Server 2008 R2 is a modest upgrade, but it is also a product of concern for companies that follow Microsoft's foray into server virtualization and those that want to deploy Windows 7 in a short time.

In particular, we have found that VMware ESX servers are easier to configure and use than Hyper-V when operating on a single managed and control cluster hosting. However, in a later example, we have to try the VMM product that Microsoft is about to launch, which should be able to handle multiple host management.

The server 2008 R2, launched with Windows 71, is the first product to be launched with Windows clients in nearly a decade. Microsoft has provided R2 with a better set of features designed to help upgrade the operating system.

These new features include the use of DirectAccess to provide security for Windows 7 customers, corporate network access that does not require VPN, and faster file sharing through BranchCache and improvements to Terminal Services sessions.

In addition to the Hyper-V and Windows 7-related changes, R2 has been improved around managing remote systems, writing management tasks through PowerShell, and reducing energy consumption.

Microsoft has not yet announced a specific price for Windows Server 2008 R2, but we expect the price to be similar to Windows Server 2008, which has launched five versions: a standard version of $999, which includes five client access licenses; An enterprise version of $3999, which contains 25 client access licenses, a data center version priced at $2999, a version of USD 2999 for systems using Itanium processors, and a network server version priced at $469.

Microsoft says its product changes include removing all Windows Server 2008 SKUs that do not have hyper-V, while client access licenses have changed, and Windows Server running Hyper-V no longer requires a specified Server 2008 Client Access License.

Starting with Windows Server 2008 R2, Microsoft has reduced support for the x86 platform while maintaining support for the X86-64 and Intel Itanium 2 processor platforms.

We tested the 2008 version of the Windows Server R2 x86-64 Datacenter version on a pair of HP servers (DL360 G6 and DL380 G6), which are used as hyper-V nodes in the failover cluster configuration. We also tested the R2 system running the domain name controller and Remote Desktop Services on the virtual machine.

The most important performance in Windows Server 2008 R2 is support for real-time migration of virtual machines. Real-time migration allows a running virtual machine to move from one node to another without having any effect on the running program. Previous Hyper-V provides a quick migration that can cause a brief pause in operations.

Hyper-V leverages the cluster Shared volumes feature in the failover cluster in Windows Server to enable real-time migration. The ability to cluster shared volumes makes up for Windows NTFS not a clustered file system.

On the good side, Microsoft uses NTFS to secure access to the available interface. For example, full access to VMware VMFS can only be done through VMware's own products.

On the other side of the spectrum, Microsoft's cluster-shared volumes have less storage hardware available than VMware's VMFS range.

Specifically, Microsoft's clustered shared volumes require the storage system to provide continuous reservation support. In our tests, this means that we cannot use Linux Openfiler iSCSI storage devices that are commonly used to evaluate cluster shared volumes. We chose to use the OpenSolaris nexentastor storage device when enabling the Sun new ComStar storage subsystem, which provides continuous reservation support for cluster shared volumes.

Once we choose shared storage, we must deal with issues related to the Windows Server 2003 Active directory domain name.

We have configured the domain name to use the Server 2003 default backward compatibility blending mode functional level. The names of our two Hyper-V hosts retain more than 16 characters, which appears to have resulted in intermittent network access failures. Until we cut the name to 16 characters, everything returned to normal.

In the shared storage and directory problems encountered, the Failover Cluster Validation wizard helps us find the fault. With regard to storage, the wizard accurately informs you of the specific steps. However, in the directory issue, the wizard's description is rather vague, and it only confirms the nodes in the same unit. And we need to choose the right object from the trial and error.

Once everything is in place, we can move the running virtual machines from one Hyper-V node to another.

We have created a R2 virtual machine running Remote Desktop Services to test whether real time migrations can truly be seamless. Configure RDS and provide services to Word 2010 as a RemoteApp, and open Word on a Windows 7 system on your network. Starting a new Word document and entering it, we start the live migration operation through the R2 failover Cluster Management console and then switch back to the document. During the migration, we noticed a pause in the remote document conversation, but none of the conversations automatically disappeared.

Real-time migrations are handy to use, but configuring processes and using this functionality in Windows Server 2008 R2 are more complex than in VMware ESX and VirtualCenter. VMware products, all of the tasks are clustered in an interface built for the purpose, and in contrast, tasks in Windows Server involve access to a variety of existing or new Windows tools.