Virtual Linux Could Be Answer To Costly Data Centers

Guru Vasudeva, enterprise chief architect at Nationwide Mutual Insurance, said during one presentation that his company plans to consolidate 600 Linux servers as virtual machines on two IBM mainframes by year's end.

The move will cut electricity use, data center space, and server costs, amounting to projected savings of $15 million in the next three years, Vasudeva said. Approximately 350 of those servers already have been consolidated. Before the project began, 78% of the company's 5,000 servers were using 10% or less of their capacity, he said.

IBM's and Oracle's pricing schemes work to Nationwide's benefit, Vasudeva said. Neither vendor points it out, but there are significant software license savings if you run their databases and middleware in virtual machines on mainframe processors. Software licenses are calculated based on the number of processors used, whether they're mainframe CPUs or Intel. "But mainframe processors are more efficient in how they manage the workload," Vasudeva said.

Security concerns about virtual machines were "addressed in depth" on Nationwide's mainframe configuration thanks to IBM's logical partitioning of the underlying hardware resources, known as LPARs, he said. Nationwide divides a mainframe running Linux virtual machines into four or five hardware units.

Linux software virtualization erects another security perimeter, subdividing an operating system/application bundle into a virtual machine with software boundaries. An LPAR unit can host dozens of virtual machines. One can stall or even come under attack and the others should remain unaffected, Vasudeva said. Nationwide's IBM mainframes run Novell's SUSE Linux version 9.

Risky Business?

Attendee Jean-Christophe Petit, IT director for Syspark, a Montreal hosting service, says his company is experimenting with Linux and Windows virtualization on its servers but hasn't adopted an approach to put into production.

Petit listened to CEO Peter Levine of XenSource say his company this week will launch a virtualization product, XenEnterprise, aimed at making it easier to build virtual machines based on Xen 3.0 open source code. Levine boasted that while only 6% of data centers have been virtualized, XenSource intends to virtualize the remaining 94%.

Petit agrees virtualization needs to be easier to implement, but he's not convinced Syspark should bet its chips on Xen. "What's the business plan behind XenSource? Where's the structure?" he asks.

Virtualization products from XenSource's proprietary competitor, VMware, "cost a lot of money, $5,000 for a two-processor server, but VMware is very solid," Petit says.

And as a mixed Windows and Linux shop, he's inclined to wait and see what Microsoft could produce with its Viridian hypervisor software scheduled for late 2007 or 2008.

A failed Windows server requires Syspark to migrate the software to the same type of hardware to avoid compatibility problems. "It's a four-hour job at least," Petit says. With virtualization, whether from XenSource, VMware, or Microsoft, that job could be accomplished in minutes with little finickiness over where the application/operating system combination landed. Virtualization, he adds, "solves a lot of problems."