James over at the Wisdom of the Clouds blog recently wrote a blog about “Why virtualization is shaking up IT data centers“, it is an interesting read and well worth taking five minutes over. he (as always) makes some great points and brings up the “car” analogy. This is an ok analogy for virtualization and it is worth extending to try and explain the benefits a bit further.
In James’ article he writes:
Virtualization, however, is a little like standardizing the driving controls on automobiles, allowing the same human to operate a wide variety of vehicles. In the automotive world, such standardization allows vehicle manufacturers to build complete, operationally ready “systems” to meet the demands of numerous drivers.
Which is right, virtualised servers are all basically the same no matter what software platform you use to virtualise them. There are small (sometimes large) differences between a VMware and a XenServer virtual machine, but all in all they are the same. This fits the analogy though; this is like having a fleet of cars, some are Automatics some Manuals. But the underlying principles are still the same. Accelerator pedal, brake pedal, steering wheel. or in Virtual machines; virtual hard disk, virtual cpu, etc.
Often people debate and worry about which virtualisation platform they choose, and for good reason. Just like choosing a brand of car for the company car fleet; there are financial and business implications to consider. In Virtualisation, you might look at VMware and call it the BMW, costs a bit more, but it is a more comfortable drive. Alternatively, perhaps XenServer is the Ford and KVM the equivalent of paying your staff a car allowance.
Your decision needs to be made, just like with company cars, not on the technical comparison alone. You need to look at the other issues such as what staff want, what has the best support, what has a local support option, which is cheapest, etc. You also need to consider how they will be maintained, who will maintain them, where, how much?
Of course, the big decision is what colour to buy?
