Frank Sabatelli believes in virtualization, but his customers don't always share his faith.
Sabatelli is vice president of virtual technology at iQor in New York City, which runs call centers for financial services firms. The idea that one client's software application would run in the same physical server as a competitor's, even in separate virtual servers, has created some resistance.
One large financial services firm configured its own server, locked it down and delivered it to iQor to run. "And don't touch it," the client ordered, according to Sabatelli.
"What I did in that instance was convert the physical box over to a virtual box without their knowledge," Sabatelli recounted during a VMware customer panel at the VMworld 2007 this week. "They came back later and asked, 'Is everything OK with the box?'"
Once the client was satisfied things were in order, Sabatelli confessed that he had converted the firm's server to a virtual box. "And he said, 'It's a what?'" Sabatelli recalled.
Such confusion is not uncommon.
Advocates tout the ability of virtualization technology to improve server utilization, save energy and simplify disaster recovery, but it is not mainstream technology. In addition, it can be a disruptive addition because it affects IT planning, processes and the corporate culture.
"This is a new model in how their IT is organized," said Diane Greene, CEO of VMware, at the conference.
Before virtualization, a department seeking more computing resources had to get budget approval, order, wait, receive and then install the new equipment. With virtualization, a new application can be provisioned in minutes without additional hardware expense. As a result, "these virtual machines just proliferate," Greene said.
The ease of provisioning that virtualization provides, however, doesn't erase other server management challenges. Physical server sprawl is simply replaced with virtual server sprawl and its own headaches.
"The biggest challenge in going to virtualization is management," said Greg Smith, director of dynamic services for T-Systems, the business services division of Deutsche Telekom.
"With virtualization you've made your world more complex, you have more variables," Smith said. While lauding VMware's management tools, he said other tools only manage one function or another and he hopes industry standards evolve.
One area, in particular, where better tools are needed is calculating chargebacks, said Chris Dickson, vice president of marketing for virtualization metering software maker Virtugo.
Before virtualization, individual department applications ran on separate servers, making IT billing relatively simple. But with virtualization, they could all be on one physical server in virtual machines. As utilization fluctuates for each application over time, calculating chargebacks gets complicated.
In addition, Virtugo finds companies can have trouble determining the appropriate number of virtual machines to put on each physical server. Some try to run too many virtual machines on one server, slowing down performance and endangering service-level agreements, while others run too few, Dickson said. One major U.S. bank limits its server consolidation to 3:1.