In virtual environments, the question of VMware or Microsoft Hyper-V is usually posed as an either/or proposition. But for a growing number of IT departments, things aren't so black and white. For better or worse, an increasing number of IT managers run a mixed virtual server environment that includes VMware and Hyper-V.
When it comes to heterogenous virtualization, organizations often "won't even know they're doing it," said Andi Mann, the research vice president at Enterprise Management Associates. But the issue of mixed virtual environments is coming to the forefront these days, as Microsoft positions Hyper-V R2 as a viable alternative to VMware vSphere.
"There's certainly a lot more swap-out migration activity now that Hyper-V has IT's blessing," Mann said. "And there's a movement toward re-evaluating VMware."VMware to Hyper-V in virtual environments
For some IT shops, running multiple virtualization platforms is a temporary situation, as the organization transitions from one platform to the other.
OSIsoft LLC, a San Leandro, Calif.-based real-time software vendor, is moving its back-office servers from VMware ESX to Microsoft Hyper-V because of cost.
As new systems come online, Barry Barnett, the senior systems engineer at the firm, adds them to his Hyper-V environment. At the same time, he is in no hurry to migrate VMware workloads, because he has several years of VMware maintenance left. The result: a heterogeneous environment for the time being.
These days, "being heterogeneous is not an issue," Barnett said. "Back in the seventies and eighties, if you had a mixed-mainframe environment, vendors would point fingers at one another, but I haven't seen that in the x86 world."Heterogeneous environment status quo
For many, running both VMware and Hyper-V could be a reality for years to come.
Joyce Meyer Ministries, an evangelical Christian church, runs VMware on its U.S. servers and a mix of Microsoft Virtual Server 2005 and Hyper-V in its 15 foreign offices.
Two years ago, as the ministry ran up against space constraints in its St. Louis, Mo., data center, it began virtualizing. A Microsoft shop, it considered Hyper-V at the time but believed that the hypervisor lacked the necessary features, and the church didn't have the in-house technical expertise to set up Hyper-V. So it chose VMware for its U.S. virtual environments, said Jonathan Smith, the church's technology infrastructure manager.
"The cost difference between Hyper-V and VMware is a night-and-day difference," Smith said. "But given the importance of the data, we figured the cost was justified."
The ministry runs some 110 virtual machines (VMs) on four Dell R905 hosts in its virtual server environment and hopes to add a few more to virtualize its remaining 60 physical servers.
The ministry's plan is to stay on VMware for the three years remaining on its maintenance contract and then re-evaluate Hyper-V and VMware, Smith said.
"We're very conscious of any spending that we do," Smith said. "But at the same time, Doug and Joyce [Meyer] understand the value of having something solid and having something up."
While the ministry may switch from VMware to Hyper-V in three years' time, "maybe VMware will have changed their model and made it more competitive," Smith said.
Mixed virtual environments tougher to manage
EMA's Mann said that just because IT managers can run multiple platforms in their virtual environments doesn't mean they should.
"I don't like to see heterogeneity in any IT environment, because it makes the environment more difficult to manage," he said.
Each platform requires different skill sets, and there aren't many tools that support all the major platforms -- although they are coming, he added.
"It's organic," he said. "This is what happens when things are free; they get in."
This was first published in February 2010