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By Andrew Donoghue, 19 October 2009 16:01

NEWS

The mighty twin combination of cost-cutting (driven by the recession) and a desire to reduce IT power consumption (to tackle climate change) means virtualisation has become one of the hottest topics for the IT community, with a whole raft of associated terms such as bare metal hypervisors, virtual machines, and utilisation rates becoming standard parts of the vocabulary of the average CIO.

Virtualisation, is essentially about cutting the connection between the operating system and the underlying hardware it operates on.

This allows multiple virtual servers or virtual machines to be installed on one piece of hardware, allowing it to be used more efficiently and more economically. There are different elements to how the technology is implemented - for example the technology used to manage the virtual machines are known as hypervisors - but virtualisation is about taking the warehouse-like capacity of a server and dividing it up into more efficient and functional rooms.

The degree to which server virtualisation makes sense in a world where server utilisation rates - the amount of the server's capacity that is actually used - hover around 40 per cent is obvious and prompts the question: why hasn't it been considered before?

The answer, as with many new trends in the IT industry, is that it has. The concept of virtualised hardware dates back to the 1960s when IBM used the technique to effectively slice up the computing power of mainframes - logically partitioning. Just as that 1960's icon of motoring economy and efficiency, the Mini, has made a return in a shiny new shape recently, so virtualisation has been dusted off and retooled to meet the challenges of modern computing.

But not every organisation has made virtualisation a standard part of their cost-cutting armoury - yet.

According to analyst Gartner, only around 20 per cent of enterprise IT workloads are currently virtualised, although the analyst believes this figure could grow to 60 per cent by 2012.

According to Gartner analyst Phil Dawson, one of the reasons for this modest uptake is the incorrect notion that any piece of hardware can be replaced by a virtual machine. "You cannot 'v' everything - there is always going to be an element of managing the physical," he said.

Because some physical infrastructure has to be maintained alongside existing physical systems, this means that rather than eliminating complexity, virtualisation could be seen as introducing more.

IT departments not only have to deal with the actual hardware they have always had to maintain but now have the additional issue of virtual systems.

"You have got the virtual world and the physical world - who is going to own the end-to-end management? It is going to be a mixture of vendors, so you are increasing complexity," says Dawson.

It is also important to consider not only what to virtualise but what not to virtualise according to Dawson.

"I see some clients that are able to virtualise up to 80 per cent of their workloads but then they start throttling back because they are hitting issues," he said.

These issues often consist of transactional problems related to intensive input/output workloads as well as some databases which are not well suited to virtual environments explains Dawson.

Other impediments to a greater uptake of virtualisation are what Dawson describes as "commercial issues" which come down to vendors trying to block use of the technology to maintain their market share or push their own virtualisation products.

Another unexpected side effect of virtualisation is that organisations can get carried away with the ease of deploying virtual hardware - resulting in virtual server sprawl which analyst The 451 Group warns can undermine financial and efficiency savings from deploying the technology.

"A financial services company told us: 'Once servers were virtualised and customers determined how quick and easy it was to add servers (no longer having to buy servers and provision them), server requests started coming out of the woodwork," said The 451 Group analyst Andy Lawrence, research director eco-efficient IT.

"True power savings may not be achieved at all if server sprawl is not managed effectively. The workload can simply expand," he warned.

Still, there are many organisations prepared to attest to its financial and efficiency benefits.

For example the UK Ministry of Defence recently decided to consolidate the servers hosting websites of the Army, Navy and Royal Air Force onto a single virtualised system. Hosting specialist Rackspace says it was able to consolidated 67 servers to 12 physical hypervisors and 72 virtual servers saving money on space and energy consumption from hardware.

Other virtualisation success stories include the London Borough of Hillingdon which now runs 94 virtual servers on just three physical machines which it claims is a 97 per cent reduction in server hardware - saving it £20,000 per year by reducing power consumption from 34kWh to 1.1 kWh and an extra £50,000 per year by removing the need to expand its IT team.

On the energy efficiency front, Sheffield Hallam University is consolidating its physical servers in a move that it claims could cut annual power use by 90 per cent from 686,000kWh to 60,500kWh.

While a lot of the initial interest in virtualisation is around server systems, the technology is also being touted as panacea for not just servers but desktops and even mobile phones.

Analyst Gartner claims that by 2012, more than half of new smartphones will be virtualised. "Virtualisation can enable enterprises and consumers to easily manage and secure their phones and it can also help handset vendors reduce bills of materials and shorten development cycles to allow for faster releases," said Gartner research vice president Monica Basso.

Whether virtualisation will really take hold in the mobile sector remains to be seen but what is clear is that although the technology has attracted more than its share of hype, it will continue to have real benefits to offer those companies that manage it correctly. Deploying it successfully it seems, ultimately comes down to being able to tell the virtual myths from the virtual reality.