Automation tools are important in preventing virtual server sprawl, but IT managers have to set strict policies and enforce them to avoid unnecessary proliferation of virtual machines.
That’s the message from a panel of virtualisation management vendors that discussed sprawl at Interop Las Vegas last week. While the vendors sang the praises of their own products, they said human processes may play an even more important role than technology in controlling VM sprawl.
“We found sprawl was more of a behavioural thing than a technology barrier,” CTO and principal founder of Fortisphere, John Suit, said. “It has a lot to do with the expectations of application owners.” The most successful IT shops set clear expectations and don’t divert from them, founder and CEO of Embotics, Jay Litkey, said.
“We have enterprises with thousands of virtual machines, and they don’t have sprawl,” he said. “They’re very disciplined, they do a lot of planning, and they have a lot of processes.”
The biggest hurdle may be politics, which George Pradel called the “eighth layer” of the network stack. Pradel, Vizioncore’s director of strategic alliances, said enterprises have to set policies that virtual machines will be shut off or decommissioned if they are not in use for a certain amount of time.
Without planning, virtual server sprawl will get out of control, he said.
“If you are investing in some type of virtualisation and you haven’t [experienced sprawl] yet, you will,” he said.
Interop attendees are embracing virtualisation in a big way. An on-site survey of 120 network engineers and IT managers and executives found 55 per cent have virtualised mission-critical servers. But virtualisation caused more problems than benefits for greater than half of the respondents. The survey was conducted by Network Instruments.
Sprawl is one of the most common problems related to virtualisation, panel moderator and director for IT consulting firm Focus, Anne Skamarock, said.
Nonfunctioning virtual machines still take up memory and space, and must be controlled, she said. While virtualisation can simplify life in many aspects, including disaster recovery, panellists said it introduces many new complications.
With virtualisation “there are two layers of infrastructure”, according to CTO of Surgient, Dave Malcolm.
“You have to be able to keep track of the virtual machines’ relationships to physical infrastructure,” he said.
Maintaining performance through these layers of abstraction is another issue. The four vendors on the panel make tools that integrate with VMware and other hypervisors. If you have a small virtualisation deployment, a spreadsheet might be a sufficient tool for keeping track and managing virtual machines. But once the deployment grows large enough, a third-party management tool may be necessary, panellists said.
“When you’re over 100 VMs, you probably ought to be looking at an automation solution,” Malcolm said.