This is the first of a two-part article. Part 2 will be published tomorrow.

For data centre managers, nothing spells "doom and disaster" quite like a server infrastructure change. Whether it's a new virtualisation technique, an upgrade to network access-control software or new command line parameters -- enterprise server management is a daunting proposition.

But what if those changes occur all at once? That's the scenario with Windows Server 2008 (WS2008). Formerly known as Longhorn, WS2008 is set to be released later this year. This week, Microsoft made available the Community Technology Preview of the operating system, which includes installation and some other options in addition to what's available in the Beta 3 release.

When it does become available, WS2008 will definitely have an impact on the infrastructure of most large companies, at least at some point.

The question is, How much of an impact will it have?

The answer depends greatly on when you start planning, how quickly you deploy and which WS2008 features you want to make part of your technology infrastructure.

For example, Continental Airlines is using a phased implementation strategy. The company started working with Microsoft early, testing the server operating system in the airline's own data centres and evaluating the release in Microsoft test laboratories in Redmond.

Continental travelled up to Microsoft at the end of April and tested the schema extensions and deployment with Continental's main Active Directory database file. "We created our entire forest architecture in the Redmond lab," says Jason Foster, a systems architect and senior technology manager at Continental. A forest architecture is a type of networking model, in this case for Continental's Active Directory structure.

The key for Continental is that it will control which services it will deploy, and when.

"We are taking a phased implementation approach where Phase 1 is limited to 10 Active Directory domain controllers in the Houston data centre," Foster explains. "We feel that phasing in the technology helps absorb some of the exposure, while adding the 10 new servers to the infrastructure allows the existing Active Directory to provide authentication services uninterrupted," so the company's security exposure is limited as it begins rolling in the new operating system.

In addition to the phased approach he described, Foster plans to deploy the Read Only Domain Controller (RODC) capability right away in most of Continental's regional locations at airports and in its two primary data centres in Houston and Charlotte. Continental will use RODC to enforce security policies in regional and remote offices and prevent unauthorised intrusions.

Meanwhile, Ward Ralston, a senior technical manager at Microsoft, downplays the coming data centre infrastructure changes.

He says that the system requirements for WS2008 are remarkably similar to those for Windows Server 2003, released in April 2003. He also says that, while WS2003 had unspecified "millions" of lines of code, WS2008 has only about 800,000. If anything, Ralston says, WS2008 will streamline IT operations with its new Server Core and PowerShell features, not add new complexity. Indeed, Foster says, some services, such as DNS, DHCP and file/print, will have little impact on data centres.

Ralston's seems to be the minority view. Christopher Voce, an analyst at Forrester Research, says that because the new server architecture in WS2008 has many important benefits for large organisations, it's best to start planning for deployment now.

"There is a host of new enterprise-level features, a new emphasis on remote management and new security improvements," says Voce. "The new Server Core feature could change the way administrators do their job. Some features, like PowerShell, look like nothing more than a blinking cursor, yet will have a dramatic impact on IT. The main point is: start testing now."

A second analyst agrees that early testing is key. "The more managers learn about how Windows Server 2008 works now, and what to expect when it is released, the better off they will be," says Brian Babineau, an analyst at Enterprise Strategy Group.

To help ease the deployment burden, here are eight steps to follow to prepare for the new release.

Step 1: Start testing Windows Server 2008 Beta 3

The most intuitive and important step is to download and install Windows Server 2008 Beta 3, which was released in April.

Testing should be conducted in a way that simulates the real production environment -- not just a portion of the infrastructure, says Forrester's Voce. This is true whether your company uses 18 servers or 800.

Of course, deployment timelines will vary from organisation to organisation, Voce says. Some companies are planning to wait for the first service pack for Windows Server 2008, which might appear in late 2008 or 2009. Others will wait until Windows Server Virtualisation is released sometime in 2008 before they deploy the new server operating system. A third strategy involves hardware cycles for desktops -- many large companies won't deploy Vista until the hardware catches up to the operating system, and some are following the same strategy with their servers.

Interestingly, Microsoft's Ralston suggests that many companies will deploy Windows Server 2008 as part of new server hardware rollouts. According to internal Microsoft research, he notes, only 10 percent of Microsoft customers deploy servers on existing hardware. This could mean that companies will opt to wait for budget approval and for new hardware offerings from Dell and HP Co. before rolling out WS2008.

In any deployment timeline scenario, beta testing can reveal technology incompatibilities in an enterprise setup, especially in cases involving remote management using the new PowerShell feature, Server Cores -- which provide a stripped-down version of the operating system to improve performance -- and new Terminal Services for mobile users who need to access mission-critical applications, says Voce. (In Computerworld's recent review of Longhorn Beta 3, the reviewer called Server Core the "killer feature" of the new operating system. Computerworld is a sister publication to Techworld.)

Step 2: Build a WS2008 deployment team

Beta testing can be an ad-hoc process. But as a more formal step, it's important to build a team that will specifically address WS2008 deployment strategy -- with members from all areas of IT, including networking, storage, applications and security. It's also important to include representatives of business units, facilities management personnel and company officers if possible.

"Dedicate a project team that can look at the new features of Windows Server 2008 and how they impact the existing infrastructure," says Enterprise Strategy Group's Babineau. "For example, there are some networking enhancements in the new OS and the project team should work with the networking admins to understand any impact or potential benefit. A cross-functional team can help leverage the new features of Windows Server 2008 and mitigate any risk. This also holds true for the storage teams that utilise servers for file share storage."

This is the first of a two-part article. Part 2 will be published tomorrow.