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Weighing the benefits of a Windows Server 2012 migration

A Windows Server 2012 migration can have major benefits, but wait to move to the Cloud OS until your organization knows exactly what it needs.

When Microsoft delivered Windows Server 2012, it also shipped a message: Cloud computing is the future. The first major release of an operating system since Windows Server 2008 R2's release in 2009, Windows Server 2012 offers a bundle of feature enhancements that are attractive to IT departments looking to move some workloads out of data centers.

IT administrators say they are optimistic about Windows Server 2012 yet hesitant about moving too quickly. While shops are reticent to jump onboard with a Windows Server 2012 migration -- development and applications often come first -- admins like what they are seeing in terms of features.

Then there's Microsoft's messaging about this being the "Cloud OS." Many admins are quick to reject the idea of moving all or even part of their back end to Microsoft or third-party hosting services. While those who maintain that on-premises is the way to go, Microsoft's iterations bring to data centers what the company has learned in the cloud running its Azure services.

But the jump to the latest offerings may not be the right decision -- at least not right away. Individual organizations need to determine the proper pace for migration based on their need for advanced features, on their virtualization platform preferences, and on their cloud aspirations, among other factors.

Cloud-optimized features

Windows Server 2012 brings with it a variety of features to the data center, making it possible for admins to deploy highly available cloud applications. And with features such as PowerShell 3.0, the improved virtualization hypervisor, Hyper-V, SMB 3.0 and more, the potential benefits of the latest release are irrefutable, even if some IT shops aren't ready to take advantage of them today. Let's consider some of these features in turn.

PowerShell 3.0 added an additional 2,300 cmdlets, allowing for more granular control over the operating system. PowerShell remoting allows wider control of a data center by executing commands from a remote computer.

Virtualization has made notable strides in Hyper-V 3.0, which supports 64 processors and 1 TB of memory. Introduced with Windows Server 2012, the VHDX format has a larger disk capacity and is more resilient than its predecessor.

One such feature catching admins' attention is Server Core, which allows for command-line administration. While it isn't new, it is improved. Server Core allows for remote administration, and has greater security than running the graphical user interface (GUI) environment. New in Server 2012, users can switch between the Server Core view and the GUI Server Manager view by installing a role.

These features may make Windows Server 2012 an attractive choice for enterprises looking to get more out of their server hardware.

Best practices for migration

Admins looking to upgrade in place from an older version of Windows Server should note Microsoft's requirements. If they are running 64-bit versions of Windows Server 2008 SP2 Standard or Datacenter, or Windows Server 2008 R2 SP1 Standard or Datacenter versions, admins can upgrade domain controllers in place.

There are, however, important exceptions to this. For one, Microsoft has noted a known issue that Server Core installations of Windows Server 2008 R2 will fail during an upgrade to Windows Server 2012. As a result, Microsoft recommends installing a new domain controller running Windows Server 2012.

An in-place upgrade is dependent on a number of other factors, as well. There are important hardware requirements to properly perform an in-place upgrade. An upgrade requires a 1.4 GHz processor, 512 MB minimum RAM and 32 GB of free disk space. During an in-place upgrade, Microsoft recommends right sizing because of errors that could result from not having enough free space to upgrade the Active Directory files.

Some IT shops forgo the in-place upgrade for building up a new domain controller and migrating data. For administrators like Alan Pratt, senior Windows administrator at Western Refining, an oil refinery owner based in El Paso, Texas, the better option was to use a new domain controller and migrate data.

The benefit to doing that, Pratt said, is that there was no downtime in running an install.

Pratt currently runs Windows Server 2012 as a primary domain controller on two databases and an Exchange 2013 installation. Aside from a bug where some users' logon scripts would not function, Pratt says that, in the six months since installation, his Windows Server 2012 machines have run without a hitch.

Pratt said he won't install new versions of operating systems in a production environment right away, because of potential bugs that can bite early adopters. "I don't mind [testing new versions] in a lab environment," Pratt said, noting that thousands of employees rely on smoothly running servers. Downtime, he said, is unacceptable.

Since installing Windows Server 2012, Pratt said he has dropped use of the GUI and relies on Server Core for remote management, using new PowerShell remoting cmdlets. By skipping the GUI, Pratt avoids having to use Microsoft's new user interface, which he sees as out of place in a server OS.

Pain, then gain?

The jump from Windows Server 2008 to Windows Server 2012 can create friction. Inevitable downtime during the upgrade will be bothersome, and application compatibility troubles will need to be solved. Organizations willing to make that switch, however, will be glad. Microsoft promises that they will find their next upgrade to be not nearly so painful.

Interestingly, that upgrade may come sooner rather than later. Just eight months after shipping Windows Server 2012, Microsoft previewed Windows Server 2012 R2, due out by the end of 2013. Billed as a completely new build of the server product, it packs a bunch of new features. Among them is Hyper-V Network Virtualization, which helps enterprises implement a software-defined network and can bridge apps to the cloud. Improvements to Storage Spaces will allow applications to run on different storage disk types.

With most Microsoft shops just now testing Windows Server 2012, many question this new rapid release strategy. Even with the load of attractive features, many admins are using Windows Server 2008 or Windows Server 2008 R2, and some even Windows Server 2003.

When Windows Server 2008 R2 went 64-bit only, many enterprises were left behind in the upgrade process until they made a decision to move to new hardware.

Despite this, Microsoft is confident in its more rapid release cadence.

"We want to give our customers the opportunity to deploy our capabilities whenever, as fast as possible," said Jeff Woolsey, principal program manager of the server and cloud division at Microsoft.

At the same time, Woolsey says the company is working to ease the upgrade process with features like Hyper-V Live Migration, which promises no downtime during a VM upgrade from Windows Server 2012 to 2012 R2.

For administrators like Pratt, a more seamless migration process would be welcome news. In fact, Pratt says he would consider doing a live migration from Windows Server 2012 to Windows Server 2012 R2 sometime after it ships in late 2013.

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