Virtualization-what is it and why bother?


Microsoft & VMWare are the two big names in Virtualization at the moment, and it’s a topic everyone is talking about. Manufacturers, resellers, consultants, analysts, end users, Jeff down the pub..they’ve all got something to say about Virtualisation. There are all kinds of facts and figures going around, some of which seem contradictory but as with most things it all depends on viewpoint..

You might be wondering why I think it’s time to add my voice to the crowd so let me tell you. At work I see a number of people, our sales guys and our customers, who know the should be thinking about virtualization and talking about virtualization, but they don’t know what they’re supposed to think and say..they know that people can virtualize..but they don’t know why, or how. They know it reduces costs but if someone asked them, the would have to hope that “Err, erm, well..” translates into something better in one of this world’s many languages!! ;-)

So in a nutshell, I hope this post/blog will become a safer, calmer haven for people to take a look at virtualization without the often deafening clamour of their colleagues, bosses and suppliers. I’ll say straight away that I’m a Microsoft Partner and supporter so I will lean towards Hyper-V but I will aim to keep everything well balanced and as neutral as possible :-)

What is Virtualization?

Virtualization has been around since the Mainframes of the 70’s but has only become a general topic relatively recently (around 2005 it really took off).

A very common, entry level example of Virtualization is hard drive partitioning. You have one physical drive, but you can divide it up into 2 or more virtual drives and that’s what the computer sees.

The big buzz around Virtualization is…

Server Consolidation.

These days, many companies suffer from “Server Sprawl”, where they have large numbers of servers, often performing just a single task (Exchange Server, File Server etc) and wasting a lot of internal resources such as RAM, storage space and processing power as well as external resources like floor space, cooling and power.

This is where Server Virtualization comes in. Tools such as Microsoft Hyper-V, VMWare ESX, Citrix XEN and more all allow you to consolidate these various servers onto one physical server running multiple virtual instances or Virtual Machines (VM’s).

Each VM has it’s own Operating System (OS) and applications installed on it and is completely separate to the other VM’s, just like physical servers. (The “One Point of Failure” discussion is later..). It’s widely accepted that most physical servers are running at about 10% utilization, so each server is wasting 90% of it’s storage, RAM, processing power etc..all things that you’ve paid (and are still paying) for. This means you could put say 7 of those servers onto one box, and that machine would then run at around 80% utilization…immediately increasing your Return on Investment (ROI). If you can go from 7 to 1, you can go from 70 to 10 which all of a sudden is a huge difference…

Getting rid of all those servers will reduce the amount of cooling and power you use in your server room/data centre too. This leads us to..

Green IT:

Gartner say that the average company spends 4%-7% of their total IT budget on energy costs such as power and cooling. If your budget is £500,000 that’s £20,000-£35,000 a year, so if you can reclaim say 40% of that and add £8000-£14000 back into your budget straight away, that’s got to be a good thing. With the continued increase of energy prices at the moment, just this aspect on it’s own can be a compelling reason to move to a virtual environment.

A virtual infrastructure can be a lot easier to manage as well. It reduces the amount of time administrators spend on repetitive tasks such as provisioning & configuring servers. If you need a new server quickly, you can simply boot up a pre-configured Virtual template and you have a new machine up and running in minutes.

There are a number of management tools such as VMWare Virtual Center and Microsoft Virtual Machine Manager which make administration even easier.