If you ask IT shops and organisations if they are using server virtualisation, I'd bet that more than 90 percent would answer in the affirmative.
But while most organisations are virtualising, many are still in the early phases, implementing the technology in dev/test or going after the low-hanging fruit such as Web, Active Directory, and file and print servers. In spite of all the features and advancements that server virtualisation offers, we're still hovering somewhere in the neighbourhood of having only 20 percent of the world's servers being virtualised. That still leaves a lot of room for growth.
So what's holding back the dream of 100 percent virtualisation among x86 servers? What are the common barriers?
In no particular order, these barriers include:
Believe it or not, even with today's widespread use of server virtualisation technologies, many ISVs either don't support their applications running within a virtual machine or may offer restricted support based on the technology being used.
In some cases, lack of support may be justified because of a technical limitation within a virtual machine, such as the need for exposing an unsupported piece of physical hardware. In other cases, it may be a political or marketing strategy to support only a specific virtualisation platform or a specific set of hardware and software. Or it could be laziness or lack of knowledge on the part of the software company in not taking the time to verify and validate that its own software works within a virtual machine environment. No matter what the reason, lack of vendor support can be a major limiting factor to widespread adoption of virtualisation.
In some cases, users are virtualising "nonsupported" applications in their environment anyway. But if something goes wrong, these ISVs are going to ask about the environment, and if the problem is happening in a virtual machine, the ISV will typically require the user to replicate the problem on a supported platform before they will offer any support. Be prepared to either fib about your environment (raise hand in jest) or have a supported physical server platform and P2V software ready and waiting to replicate the problem.
Things won't generally change or improve here without demand from end-users. If you operate any software that doesn't support a virtual environment, keep exerting pressure on the vendor until they agree.
Security and compliance
In many organisations, security concerns are usually addressed after deployment. But for many, the unknowns surrounding virtualisation are enough to keep them from moving forward with the technology or expanding it beyond dev/test and low-hanging fruit.
According to Dave Bartoletti, a senior analyst at the Taneja Group, "there's a lack of industry regulation dealing with virtual servers to date, and this leads to uncertainty about what kinds of mission-critical apps can be safely virtualised."