The promise of virtualization technology has convinced some companies to require that most new applications be run immediately on virtual machines.

Such a rush to virtual servers is certainly under way at The Hartford Life and Accident Insurance Co., where "the standard is that everything new comes in on virtual servers," said Bruno Janssens, senior architect in the company's infrastructure services group.

A dozen of the insurer's 5,000 servers are currently virtualized, as are some 500 Windows XP client machines, he said.

However, IT managers at some companies can feel forced to hide plans from users and vendors in order to overcome potential objections to virtualization, said users and analysts attending Computerworld's Infrastructure Management World (IMW) conference, held last week in Scottsdale, Ariz.

In some cases, end users object to virtualization because they're concerned that virtual machines lack the security and performance of dedicated servers.

At the same time, many IT operations must deal with vendors that either prohibit them from implementing their software on virtual machines or establish convoluted pricing schemes for the right to do so.

Companies are taking a variety of measures to overcome such obstacles, including adopting "don't ask, don't tell" policies in order to get virtual applications running without notifying users and vendors.

In the latest installment of a twice-yearly survey by The InfoPro, a New York-based consulting firm, about 40 percent of respondents from 150 large companies said they aren't asking business units for permission to implement server virtualization.

"Server pros are saying, 'I guarantee service-level agreements, and the users don't need to know how I do it,' " said Bob Gill, director of server research at InfoPro.

Some IT professionals at the conference defended decisions to keep users out of the loop, while others said such dishonest dealings could prove tricky.

"It's not like we're hiding anything," said Wendy Saadi, a virtualization project manager for the city government of Mesa, Arizona.

"The application analysts know, and they'll raise objections if they see any problems out beforehand," she said. "My users don't care what servers we run their applications on, for the most part, as long as it all works."

However, Saadi noted that an initial effort by a small Mesa IT team to implement virtualization without notifying users -- or the rest of the IT organization -- did force a change in direction.