Building a private cloud: Get ready for a bumpy ride

Computerworld - When cloud computing became a topic of discussion a few years ago, public clouds received the bulk of the attention, mostly due to the high-profile nature of public-cloud announcements from some of the industry's biggest names, including Google and Amazon. But now that the talk has turned into implementation, some IT shops have begun steering away from public clouds because of the security risks; data is outside the corporate firewall and is basically out of their control.

Tom Bittman, vice president at Gartner, said in a blog post that based on his poll of IT managers, security and privacy are of more concern than the next three public cloud problems combined. He also wrote that 75% of those polled said that they would be pursuing a private cloud strategy by 2012, and 75% said that they would invest more in private clouds than in public clouds through 2012.

Frank Gillett, an analyst at Forrester Research, agrees that IT's emphasis is more on private clouds these days. He says that IT managers "are not interested in going outside" the firewall.

Still, as Bittman's blog post points out, private clouds have their share of challenges, too; in his poll, management issues and figuring out operational processes were identified as the biggest headaches. And, of course, an on-premises private cloud need to be built internally by IT, so time frame and learning curve, as well as budget, need to be part of the equation.

Indeed, transitioning from a traditional data center -- even one with some servers virtualized -- to a private cloud architecture is no easy task, particularly given that the entire data center won't be cloud-enabled, at least not right away.

In this two-part article, we'll examine some of the issues. Part 1 looks at how cloud differs from virtualization and from a "traditional" data center. Part 2 will examine some of the management issues and look at a few shops actively building private clouds, and the lessons they've learned.

While we generally think of a private cloud as being inside a company's firewall, a private cloud can also be off-premises -- hosted by a third party, in other words -- and still remain under the control of the company's IT organization. But in this article we are talking only about on-premises private clouds.

Also, despite all the hype you might hear, no single vendor today provides all of the software required to build and manage a real private cloud -- that is, one with server virtualization, storage virtualization, network virtualization, and resource automation and orchestration. Look for vendors to increasingly create their own definitions of private cloud to fit their product sets.