Open-source virtualization: Who's biting?

Computerworld - Virtualization is unarguably one of the biggest trends of the past few years, and open-source software has been on the IT radar for a while now. So does that make open-source virtualization twice as much of a good thing?

At least some corporate IT departments think so. They're turning to open-source software as part of their virtualization mix. Sure, savings are a big factor, but so is the ability to tweak the software to suit specific requirements.

Just ask Stan Yazhemsky, manager of IT operations at Legal Aid Ontario (LAO), which uses Citrix Systems Inc.'s XenServer, a management tool running on the open-source Xen hypervisor.

XenServer's open APIs give him and his team of three Linux engineers better access to and control of advanced functions, especially security, Yazhemsky says.

LAO, a non-profit corporation that provides legal advice and services to low-income individuals, has 200 locations across Ontario and hosts three data centers. Those data centers house 239 Windows servers and 68 Linux servers. Some 95% of LAO's servers are running XenServer.

LAO has 154 terabytes of sensitive data such as client/lawyer information, financial files and individual case loads that span everything from burglaries to theft and murder. Security is a key concern. Yazhemsky says that by building monitoring tools and integrating them with the Xen platform he's been able to mitigate network attacks.

Stan Yazhemsky, manager of IT operations at nonprofit Legal Aid Ontario, says that using the XenServer hypervisor has allowed him to do a better job with security.

"If an attack manages to break into the system, our embedded script will shut down the compromised virtual machine immediately and bring another virtual machine up, in real time with no effect on users. That's something that you can't get from any closed-source solution," Yazhemsky says.

As a result, the organization is able to invest less in security than it would otherwise have to, he says. His calculation is that LAO spends about 40% less in security software and management costs than it would have otherwise, "because we can script events that proactively search for any changes," Yazhemsky says.

Open-source virtualization -- tiny but growing

Despite its fans, the overall market for open-source virtualization is very small indeed, though it is expected to grow.

"Open source is less than 5% of the overall server-virtualization revenue market share, but could nearly double by 2012," says Alan Dayley, a Gartner Group research director.

Open-source hypervisors including Red Hat Inc.'s KVM and Xen -- used by both Citrix and Oracle Corp. -- and the management tools running on top of them are gaining strength in both adoption rates and advanced features formerly found only in the likes of VMware, the virtualization market leader, Gartner says.

Gartner's 2008 figures show that for the hypervisor market -- in units, not revenue -- Citrix had 2% and Virtual Iron held 1%. For 2012, Gartner's projections are that Citrix will hold 6% of unit share, and Red Hat 2%.

Nevertheless, open-source virtualization will likely always remain a small piece of the pie. "While companies like Citrix and Red Hat are going to see great growth, they are not going to take significant market share," says Gartner analyst Phillip Dawson. "Most of the share change will be between Microsoft and VMware."

And that's a shame, says IDC analyst Gary Chen, because open-source virtualization software has a lot to offer. "A lot of people don't really know how good Citrix XenServer 5.5 has become," says Chen.

One potential huge market for open-source virtualization: cloud service providers. "If you're a large service provider and you're building a cloud, you may have very custom specific needs, [and] you may need to modify the source code and you can go with open source," Chen says.

As companies like Amazon.com build out their cloud computing strategy and virtualize literally thousands of servers in their data center, they will be looking at vendors offering cheaper virtualization solutions with well-developed management tools that they don't have time to build, predicts Bill Claybrook, a former Aberdeen analyst who now has his own technology research firm, New River Marketing Research, based in Concord, Mass.

Under this scenario, he says, Citrix's attractiveness will increase. "Citrix is one company out of all of those vendors that could make some money in cloud computing by providing a free Xen hypervisor and marketing its management tools at a reasonable price," Claybrook says.