What is virtualisation and what are its benefits? This article first appeared in "Managing Partner" magazine, Volume 9 Issue 8, 2nd February 2007.

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Virtualisation:reality

“Virtualisation” is the latest buzzword sweeping through the IT department, and unlike many over-hyped technology fads, it seems that this one really can deliver on its promises. As the 7,000 attendees of the VMWorld conference will attest, virtualisation is re-shaping the IT landscape.

The Fall and Rise of Virtualisation

Virtualisation was invented in the mainframe era of the 1960s in order to make better use of expensive computer resources. It is a technique for dividing one physical computer into several “virtual” computers, thus making it possible to perform multiple tasks simultaneously.

The technology had fallen out of favour by the mid ‘80s. For one thing the low cost of PC-based servers made mainframes irrelevant to all but the largest businesses. For another, improvements to server operating systems made it possible to undertake multiple tasks simultaneously on the same computer.

Virtualisation didn’t fade into complete obscurity however. Both Citrix and Microsoft’s Terminal Server products use virtualisation techniques to run desktop applications such as Word for multiple users on a single shared server. Forty years after it was invented however, the wheel has turned full circle and virtualisation is now solving the headaches of a new generation of server-based applications.

Too Much Power

Today’s IT department faces a new problem; computer power is cheaper than ever, but hard to make use of efficiently. Over its lifetime, your firm’s email or accounts server may only use 15% of its available capacity. This huge waste of resources has a direct impact on your firm’s bottom line.

For example, buying a fairly modest server, housing it in central London and operating it over a typical five year lifespan will cost your firm anywhere up to £10,000. Up to 75% of the money you put in to in capital investment, floor space and electricity is wasted.

Even a modest set-up of perhaps 20 servers will lose a firm £150,000 of profit over five years. This waste isn’t profligacy on the part IT department; rather it is a compromise designed to address a number of problems:

• Each server must have enough capacity to cope with peaks in demand which occur for a few hours in a day, or on a few days in a month. Your accounts server will be working at full stretch during the year-end billing run, but may spend much of the time idling along at 5% or 10% of its capacity. It will use nearly as much electrical power (and thus generate as much heat) when idle as when it is working at full capacity.
• Servers running several applications tend to be less reliable due to conflicts between those applications. Software vendors and IT teams prefer to install each application on its own server to guarantee that it will be available when the firm needs it.
• Managing the allocation of resources to different applications running on the same server is difficult. Applications compete for resources rather than being allocated them based on how important they are to your firm’s business.
• Moving an existing application that has outgrown the demands of its old server to a new one is expensive, risky and potentially disruptive to the business. IT departments sensibly over-specify servers to put the evil day off as long as possible.

Until now, the most pragmatic response to these challenges has been the “one application, one server” approach adopted by most IT departments but the result is unsatisfactory for both the IT department and the firm’s Partners.

The frustrations faced by Westminster firm Winckworth Sherwood are entirely typical. According to IT Manager Sam Luxford-Watts, “We were running out of space and available power in the server room. We were forced to purchase additional servers for each new project, yet we knew that many of the servers we already had were under-utilised.”

Virtualisation to the Rescue

At its heart, virtualisation is a relatively simple piece of software that pretends to be computer hardware. All that the IT team need to do is install some additional virtualisation software on a new server before installing the operating system in the usual manner (Microsoft Windows Server for example).

The extra virtualisation software fools the operating system into thinking it has exclusive control of the server’s processors, memory and disk drives and thus everything behaves exactly as it would in a normal installation. Virtualisation’s neat trick is that a second operating system can now be installed on the same server and it too thinks it has exclusive control of the hardware resources.

Multiple “virtual servers” can be created to make full use of the physical server’s capacity, whilst keeping each one isolated from the misdemeanours of other virtual servers on the same machine. One virtual server can crash or be re-started with no impact on its neighbours.

Just as usefully, each virtual server is entirely self-contained within a handful of (very large) files and, as we’ll see, this solves a number of previously intractable problems.

Quarts into Pint Pots

Virtualisation’s big planet (and wallet) saving benefit is that it eliminates energy-wasting equipment. The IT team can now install multiple virtual servers on a single box, and decide how much memory, processor and disk resource is allocated to each application.

Luxford-Watts reports “Virtualisation has enabled us to cut our physical servers from 22 to just seven. We found it hard to believe at first, but our systems are more responsive with less hardware, as we can now allocate resources to applications as they require them.”

Whilst the results achieved by Winckworth Sherwood are remarkable, they are by no means an exceptional case. According to Taylor Vinters’ Director of IT, Steve Sumner, “Our firm has achieved significant savings in space, power consumption and cooling requirements since we introduced virtualisation. Of our 41 main servers, half are now virtualised and run on just four physical boxes.”

VMWare, a leading vendor of virtualisation technology, estimates that its customers are currently running more than one million virtual servers, with estimated annual energy savings in excess of $560 million. Whilst that is about the same as the residents of New England spend each year on heating, ventilation and cooling, it’s just the tip of a very large (and melting) iceberg of potential energy savings.

Averting Disaster

Most applications have to be moved a new server at some point in their life. In the very worst case the equipment may have been destroyed by a fire or similar disaster, but often the cause is more a mundane problem such as breakdown or the need to move to a more powerful box as the firm grows.

Unfortunately, it is not a simple matter of copying everything from one server to another and hitting the “on” button. Configuring the operating system to support a new set of hardware is fraught with problems and the end result is often an unreliable server.

The usual solutions are either to pay a hefty premium to duplicate critical equipment at another location, or to spend several weeks re-installing everything from scratch. The latter approach never produces an exact match for the old system and isn’t an acceptable option in a disaster recovery situation.

By way of contrast, virtualisation presents a standardised set of “virtual hardware” to the operating system regardless of the underlying physical hardware. Moving a virtual server between completely different types of hardware is simply a matter of installing the virtualisation software and then copying the handful of virtual server files to the new machine.

Taylor Vinters; Sumner went on to say, “Operating from our single Cambridge site brings additional business continuity risks, and so we must replicate all key systems and data at an off-site location. Virtualisation has enabled my team to create this crucial safety net using just two physical servers located in a specialist data centre, once agan achieving considerable cost savings when compared with a traditional solution.”

In another example, one of two brand-new servers decided to break down in Kennedys’ recently opened Sydney office. It took us a matter of minutes to transfer all the virtual servers from the failed server to the remaining one. The fault was repaired and the virtual servers copied back again with no material impact on the firm’s business.

Virtualisation gives everyone the opportunity to achieve a level of resilience that was hitherto the preserve of only the largest firms. An entire IT set-up can be replicated using very modest amount of equipment and time.

Far-flung Outposts

The project to launch the Kennedys Sydney office also illustrates further benefits of the “hardware agnostic” nature of virtual servers. Flying out a large team of IT staff and suppliers to set up the systems for the new office was ruled out on grounds of cost and practicality. From previous experience, we knew that installing everything on hardware in the UK and then shipping it overseas was equally costly and would miss the opening deadline.

The solution was to build a set of six virtual servers in the UK using our experienced staff and suppliers. This enabled us to create a system of the highest standard and prove that it was fully working. At the same time a local IT supplier in Sydney procured and set up a pair of suitable servers plus the virtualisation software (in this case a product from VMWare).

The fully tried and tested virtual servers were copied to a backup tape and couriered down under. Three days later we had a the complete system up and running, right on schedule and for about 30% less than our cost estimates for a more traditional approach.

What’s more, because the virtual servers are just files, the process can be repeated effortlessly. According to Luxford-Watts “We set up all of our new servers by copying existing templates. We can create a new server in minutes with no set-up or configuration errors, which has drastically cut time to install new applications and upgrades.”

It is easy to see how having a complete set of IT systems packed and ready to go would save time and money in other scenarios, for example in a merger situation or the set up of a litigation support system for a major case.

Security Headaches Cured

One of the biggest headaches for any IT department is dealing with the increasing pace at which new security vulnerabilities are exploited. Major threats to the firm’s IT systems require the team to respond in a few hours or minutes rather than days or weeks. Since most specialist legal applications have exacting set-up requirements, the rush to address a new security threat carries a significant risk of breaking the very thing one is trying to protect.

Virtualisation makes it possible to take a copy of an existing server, apply a security patch and then test it in an isolated environment within a few minutes. If no problems are discovered, the updated server can be copied back in to the live system immediately.

According to Sumner, “Virtualisation has released us from this Catch-22 situation. We can maintain a high degree of security, whilst at the same time being confident of recovering immediately from unforeseen problems caused by a new security fix. For the firm’s partners, ensuring that systems are available when needed is far more important than any cost savings that we have achieved.”

The ability to quickly copy, update and test is also proving useful in more routine tasks. Luxford-Watts added “We were able to completely mirror our live email system on a test network and upgrade it to a new version without the need to purchase additional equipment. This entire upgrade was completed without any interruption to service.”

The Main Players

Unsurprisingly, virtualisation is the new battleground for software corporations and it is far too early predict who will emerge as the eventual winner. The two front-runners are Microsoft and VMWare (a subsidiary of computer storage giant EMC), with a whole host of others vying for a place at the head of the pack.

VMWare has a clear advantage in the speed with which it has innovated, helping it to grow from a start-up to a serious global player in just seven years. Offering a comprehensive range of in-house and third party-software for smoothing the transition to and managing the operation of a virtualised environment has made it a clear favourite with overworked IT managers.

Microsoft has been perhaps less innovative and is pursing its favourite market-domination strategy of buying up innovative technology companies, application virtualisation specialist Softricity being the most recent example. These newly acquired products are quickly assimilated and released at a low cost or as add-ons to Microsoft’s lucrative software assurance agreements.

Both main players have a range of products covering both the desktop and server virtualisation spheres, including a number of free products aimed at those dipping a toe in the water. VMWare’s more cohesive product range certainly inspires fervent devotion amongst users as witnessed at their VMWorld conference. The event was likened by some to a “Californian love-in for IT folk.”

Having a better product doesn’t guarantee success against Microsoft however, as erstwhile server giant Novell can attest. Regardless of the current uncertainty, virtualisation is being adopted rapidly by firms both small and large. The range of benefits obtained with little or no disruption makes it irresistibly attractive to both IT managers and Partners with an eye on the bottom line.

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