By Jason Compton

Server virtualization broke away from the mainframe to join the now ubiquitous x86 server environment around the turn of the millennium, when a small company called VMware started a quiet revolution in the data center. Since then, other key players, including Microsoft and Xen, have staked their claim to this fast-growing opportunity. Even AMD and Intel are beginning to shift their chip designs to better accommodate the growing desire to run not just multiple application servers, but multiple operating systems, on workaday enterprise technology platforms. In the initial stages, the virtualization value proposition focused on consolidating fleets of aging Windows NT servers on smaller, consolidated machines. Now, virtualization has evolved to play a major role in continuity planning and reliable computing.

This means that your data center may already employ virtualization. If it does not, change is coming soon. The proportion of servers shipping with virtualization software will more than triple from 2005 to 2010, predicts IDC. And a recent survey by The Strategic Council indicates that most organizations are either using or planning to deploy virtualization. The earlier CIOs can articulate both the need for and the benefits of virtualization in their organizations, the better prepared they will be to see tangible rewards.

"If you're looking for higher service availability and better delivery of service to the business, along with business continuity, those are the things virtualization can deliver," says Tom Hayes, VP product marketing at CA. "If you talk to virtualization customers, you find that delivering services reliably and within expected and agreed-upon Service Level Agreements is clearly ahead of costs in terms of importance."

In a study conducted by The Strategic Council in cooperation with CA, IT decision makers rated reliability, business continuity, utilization and responsiveness ahead of controlling server hardware costs, with managing administrative costs even farther down the list of reasons to adopt virtualization. "The strongest finding from the survey is that many people are adopting virtualization for the right reasons. Enterprises need to improve uptime, performance and reliability, and virtualization aligns well with those needs," says Paula Daley, CA's VP of product marketing. Companies that realize measurable cost savings tend to find them substantial; nearly three quarters of those with recorded cost savings had at least a 10 percent improvement in server operation expense.

Real Rewards
But reliability, performance and continuity are proving far more critical to adopters. "Many customers are using virtualization to reduce the complexity of disaster recovery, because virtual machines speed up software provisioning," says Raghu Raghuram, VP of product and solutions marketing at VMware. "Normally you would have an identical server for primary and backup uses, because that's the only way you can make sure your backed-up images and applications will [appear] in a disaster recovery scenario. Virtualization allows you to have primary hardware that is very different from the secondary hardware."

Conventional servers are often stockpiled with expensive, exact duplicates to avoid any conflict during an operating system or application migration. Virtual machines always appear to be the exact same hardware platform, allowing one server instance to be moved to any new host without fear of conflict.

A single virtual machine can be configured and deployed in less than a day — but a virtualization strategy is necessary for larger projects and will take a bit more time and planning. Nearly 90 percent of virtualization users reported needing more than one month to roll out their server virtualization projects, and almost half needed at least six months (see chart below).

"It's a lot easier to back up these virtual machines, move them across to a new location or new server, and restore them, than it is to work with a normal machine," says John Winter, CA senior alliance manager. "But it also means that you need to be thinking about more than just the operating system virtualization with these environments. You need management tools that deal with multiple-vendor virtualization products to ensure that your virtual machines are always available and always easy to access."

Warren Shiau, lead analyst of IT research for The Strategic Council, notes that administrative costs, provisioning and application deployment were not rated important by survey respondents, which he attributes in part to a lack of understanding of virtualization management techniques. Companies using robust controls for the management of their virtualized server assets will have an easier time articulating day-to-day benefits from virtualization — in addition to the comfort of reliable, easily deployed disaster recovery tools.

Important to any virtualization strategy is the realization that virtual machines not only have the same resource management requirements as would a stand-alone server, but their own unique administrative privileges and management considerations as well. "You need to be able to keep track of your virtual machines as well as the relationships to physical machines, and that means being able to measure and manage them. Otherwise, the result may be virtual server sprawl," Daley says.

Long-Term Success
As the number of virtual machines in organizations continues to grow, treating those environments as if they were physical computers can be crucial to long-term success. "Now that it's so easy to create a virtual machine, you can see a need to have sophisticated management software and to make sure that there is a system for managing, archiving and keeping track of the virtual machines," Raghuram says.

The increasing ease of deploying virtualization software and the ever-growing capacity of powerful new servers mean that the technology will only grow in popularity. Virtualized servers can be an integral part of your IT infrastructure when given the same care and integrated management attention as the rest of your IT environment.

Jason Compton is an enterprise technology writer based near Madison, Wisc., and the author of VMware 2 for Linux (Prima Tech, 2000). His writing has appeared in more than 40 publications.