Virtualisation can be a great boon to any IT department but, according to Gartner analysts it brings with it potentially nasty side effects.
David Coyle, research vice president at Gartner, detailed the seven side effects at the research firm's Infrastructure, Operations and Management Summit, in Orlando.
While virtualisation promises to solve issues such as underutilisation, high hardware costs and poor system availability, the benefits come only when the technology is properly applied and consistently monitored for change, said Coyle.
According to Gartner virtualisation is not an IT cure-all because of:
- 1. Magnified failures. In the physical world, a server hardware failure typically would mean one server failed and backup servers would step in to prevent downtime. In the virtual world, depending on the number of virtual machines residing on a physical box, a hardware failure could impact multiple virtual servers and the applications they host.
- Degraded performance. Companies looking to ensure top performance of critical applications often dedicate server, network and storage resources for those applications, segmenting them from other traffic to ensure they get the resources they need. With virtualisation, sharing resources that can be automatically allocated on demand is the goal in a dynamic environment. At any given time, performance of an application could degrade, perhaps not to a failure, but slower than desired.
- Obsolete skills. IT might not realize the skill sets it has in-house won't apply to a large virtualised production environment until they have it live. The skills needed to manage virtual environments should span all levels of support, including service desk operators who may be fielding calls regarding their virtual PCs. Companies will feel a bit of a talent shortage when moving toward more virtualised systems, and Coyle recommends starting the training now.
- Complex root cause analysis. Virtual machines move -- that is the part of their appeal. But as Coyle pointed out, it is also a potential issue when managing problems. Server problems in the past could be limited to one box, but now the problem can move with the virtual machine and lull IT staff into a false sense of security.
- standardisation. Tools and processes used to address the physical environment can't be directly applied to the virtual world, so many IT shops will have to think about standardising how they address issues in the virtual environment.
- Virtual machine sprawl. The most documented side effect to date, virtual server sprawl results from the combination of ease of deployment and lack of life-cycle management of virtual machines. The issue could cause consolidation efforts to go awry when more virtual machines crop up than there are server administrators to manage them.
- May be habit forming. Once IT organizations start to use virtualisation, they can't stop themselves, Coyle said. He offered tips to help curb the damage done from giving into a virtual addition.