A funny thing has happened on the path to virtualization Nirvana: We've stopped, or at least greatly slowed, our progress toward highly virtualized data centers. Gartner says that just 16% of data center loads are virtualized, and our own survey shows ambitions for virtualization are actually backtracking. We set out to find some real-world virtualization "success stories," just to remind ourselves why we went down this road in the first place. Capital equipment savings and greater operational efficiencies have been the promise, but are they being achieved?
The answers, when answers are available, are varied. Some companies haven't slowed down their implementations long enough to measure the results they're getting. "We don't know what the savings are. We just know they're there," is a common response.
At the same time, our InformationWeek Analytics survey found that 35% of respondents say they expect to virtualize less than 25% of their data centers by 2011. That finding reflects either a less optimistic or more realistic assessment than survey respondents exhibited last year, when only 22% took that stance.
The reasons are legion. The ability to easily generate virtual machines tends to lead to a willingness to do more, and soon the IT manager finds virtual machine sprawl on his hands. As concentration builds up, performance and management problems emerge. Monitoring systems need to check not only whether a virtual machine is running, but also whether resources allocated to it match the VM's needs. In some cases, overallocation shortchanges operations elsewhere.
Then as the number of virtual machines per host server increases, I/O problems start to develop. I/O is the next chokepoint in virtualization. Cisco, working with VMware, built a network fabric to address this issue and entered the server market in 2009 with its Unified Computing System. Hewlett-Packard responded with the BladeSystem Matrix. Meantime, third parties had already spotted the issue. Xsigo, with its I/O Director, and others seek to virtualize the I/O and move it out of the hypervisor's virtual switch onto a hardware device, where packets are separated into their respective storage and network destinations, relieving the host server of work.
As we shall see, management tools are paramount once the virtual environment is generated. Our four case study examples ignore the 25% ceiling revealed in our survey; they're for the edification of those seeking much higher levels of virtualization in the data center and demanding a greater return on their virtualization investment.
Orchard Supply Hardware
When Moon Son, director of IT infrastructure at Orchard Supply Hardware, a California chain of 91 stores, became head of the company's data center in 2006, he realized immediately he would have to rebuild from the ground up around virtualization. His new employer had a shopping list of 33 projects it wanted him to undertake on top of an aging infrastructure, such as establishing two new financial systems and a PCI compliance system. For starters, he chose to phase out 30 servers, replacing them with new standalone and rack-mount models from Dell. He virtualized 13 host servers, and in the end, tripled the number of production systems to meet expanded company goals.