March 31, 2011, 5:51 PM — More than three quarters of U.S. companies virtualize at least some of their x86-based servers, but few get their full money's worth out of virtualization efforts--due to management blunders, analysts say.
The biggest misconceptions focus around three issues: how closely to manage virtual machines, how to plan the capacity and workload of the virtual infrastructure and how to go beyond technical configuration to keep operational costs from running out of control, according to analysts.
Here is some food for thought regarding the top 5 money-gobbling mistakes, spanning technical/operational, management and planning, and budget issues.
1. Underutilization of Physical Servers
The most direct reason companies fail to get the best return on their virtual infrastructures is that they don't run enough virtual machines on every physical server, according to Galen Schreck, principal analyst at Forrester Research, who specializes in management and implementation tools for virtual architectures.
"For a long time people kept the ratio of VMs per machine low to avoid degradation of performance," he says. "They didn't want the systems to balk, so they decided they'd be satisfied with the savings they got running at 50% utilization, or only putting 10 VMs on average on a server."
In 2009 or early 2010, that was a reasonable approach, because performance-management tools gave a poor picture of how well VMs were running inside a physical server, says Dan Olds, principal of Gabriel Consulting Group, who has been doing annual surveys of Windows and Unix-server users for more than five years.
The percentage of servers within corporations continues to grow, but the level of satisfaction of the companies using them has been flat for several years, indicating they're not getting all they hoped from the new technology, he says.
Being satisfied with a set utilization percentage or level of consolidation of physical servers to virtual "leaves money on the table," Schreck says. "A lot of companies seem like they're just being cautious not to risk pushing servers to the point performance might not support an SLA during a spike, so they're not raising utilization high enough."
2. Failing To Push VM Management Tools Harder
It's easy enough to cram more VMs on a single physical server and get a higher return-on-investment for virtualization spending, Schreck says.
That doesn't really solve the problem, though.
Current performance-management tools such as Microsoft's Systems Center Virtual Machine Manager and VMware's vCenter Server have capabilities that are light years ahead of two or three year-old tools, but key metrics such as whether the new infrastructure is easier to manage than the old one have not changed, Olds says.
"It's not clear how many people are actually using the tools," Olds says.