What is virtualisation?


You might have heard us here at Correct talking about virtualisation and how much more efficient it is for your business. But what, in simple terms, is virtualisation?

The traditional method of installing computers was to obtain PC hardware and then install an operating system on it followed by a number of applications. Although it may not seem like it sometimes, most of the hardware on which software is installed does little else than simply ticking along at only a few percent of its total capability. Even server machines spend most of their time waiting to do something.

This means that there is the opportunity to have physical machines doing much more than they are currently. What if you could run two different operating systems on the single piece of hardware? That would provide much better utilisation and flexibility of the purchased hardware.

In an nutshell this is what virtualisation is. By installing a virtualisation host on a piece of hardware first, it allows the installation of an number of virtualisation guests on that same piece of hardware. Thus, rather than having to have two separate physical server machines, you could use only a single virtualisation host running two virtualisation guests to achieve the same thing.

The clever thing with virtualisation is that the guest operating system has no real idea that it isn’t running on dedicated hardware, that is what the virtualisation host takes care of. It intercepts requests to physical items like hard disks by virtualisation guests and routes them to the actual physical hardware. It does this at the same time as managing requests from other virtualisation guests running on the same machine.

Thus, with virtualisation you can now have multiple virtual machines running on a single piece of hardware. This greatly increases the utilisation of the base hardware and is much more cost effective for most businesses.

Virtualisation is now so popular it is even built directly into the latest desktop operating systems like Windows 8. Why would you need virtualisation in a desktop operating system you may ask. The major reason is that it allows you to run older versions of software that may not be able to operate on the latest operating systems.

Because virtualisation guests are abstracted from the actual hardware on which they are running, migrating and upgrading these guests is much easier since they don’t really care what physical hardware they run on – the virtualisation host takes care of all that. So now rather than an upgrade being a complete reinstall of everything, it is typically just a copy of the guest from one virtual host to another.

It is expected that because virtualisation provides such improvements in utilisation that its use will continue to grow, even down to application in mobile devices. Although you may not see virtualisation in operation, chances are that your business is already taking advantage of the benefits that it provides.