Unless you’ve been living on another planet for the past couple of years, you’ll no doubt have heard and read about virtualisation, the technology that lets you run multiple virtual machines (VMs) on the same physical PC or server, each with its own operating system and application software.

What you won’t have seen, however, are very many practical examples of things you can do with virtualisation, beyond tinkering with an OS. I want to address this omission and show you how to use virtualisation to quickly build and use a network-attached storage (Nas) appliance.

Why a virtual appliance?

Of course the first question you’re bound to ask is why you would want to use virtualisation to do this. The answer is because it makes the process a whole lot easier, eliminating many of the issues and concerns associated with more conventional approaches.

For example, the Nas software we’ll be using here is written for FreeBSD Unix, but that doesn’t matter as virtualisation lets you install and run more or less any operating system on either a Windows or a Linux PC.

Importantly too, virtual appliances come already installed, with the necessary operating system (typically a Linux or, in this instance, Unix variant) plus all the application components required. All you have to do is start up the virtual machine and you’re away with, in this example, a built-in web interface to configure the Nas file sharing to suit your network.

Plus you don’t have to worry about compatibility as it’s all virtual and everything you need is supplied ready to run. Indeed, this particular Nas appliance comes with a virtual Raid 5 disk array, but the PC involved only needs one physical disk drive. And it doesn’t matter whether it’s Pata (Parallel ATA), Sata (Serial ATA) or even SCSI.

Virtually equipped

Not convinced? Well let’s just run through this deployment starting with the virtualisation software itself, which can be obtained in a variety of formats from a number of sources.

Most let you create and customise virtual machines of your own, but I’ve opted for the VMWare Player. This lacks virtual machine building tools but enables you to run already created VMs without having to know too much about what’s involved.

Another benefit is that it’s from the market leader in virtualisation, VMWare, so there are lots of pre-built virtual appliances you can download to run on it. Added to which, it’s available for free – which is always an important consideration.

Download the player
VMWare Player is available for both Windows and most Linux distros, but if you’re running Windows, you’ll need Windows 2000 or, better still, XP.

A fast processor will also make life easier (500MHz or better is recommended) plus you’ll need plenty of memory. The minimum you can get away with is 256MB, on top of which you should have enough to host any guest operating systems.

Similarly you’ll need plenty of disk space as virtual machines can be several gigabytes in size. However, they can also be quite small, as is the case with the Nas appliance we’ll be using here.

To get hold of the VMWare Player simply go to the VMWare website and find the download page for the platform you’ll be using. I’ve used VMWare Player V1.02, a 28.4MB download, which can be installed like any other Windows application, although may take several minutes. Plus you’ll have to reboot once it’s finished.

The virtual appliance
The next step is to download the virtual appliance. The product I’ve used here is called FreeNAS and, as the name implies, it can be downloaded for free from www.freenas.org

You’ll find the software available in two formats; either as a complete install disk with which you can set up a FreeNAS appliance from scratch or as a VMWare virtual appliance. Either way you’ll end up with exactly the same appliance functionality, but by opting for the VM implementation most of the hard work is done for you and there are no compatibility worries.

I used version 0.671 for this workshop, downloaded as a 19.2MB compressed file, which I then unzipped into a folder on my PC hard disk (C:\FreeNAS_VM).