Ask any data centre manager to list his or her biggest challenges at present, and, in most cases, a cluster of related concerns will top the list: provisioning and managing a large number of new servers; managing heat and power; and dealing with a shortage of space – these are the troubling by-products of rapidly rising demand for new applications and services.
This is what makes the case of Alstom – one of the world's largest industrial concerns, building power plants, trains and ships – so unusual. Until very recently, Alstom's UK business went for 18 months without buying a single low-end server – in spite of its growing business and rising demand for its services. Its European data centres have plenty of physical capacity, it has no overheating problems, and its management costs have been falling.
Equally impressively, Alstom can boast one of the fastest server provisioning speeds in business today. "We now provision a new server within an hour – instead of the month it used to take," says Rob Jones, Alstom's director of technology for Northern Europe.
How is this achieved? The answer, of course, is virtualisation – the process of separating the stack of software which provides end user services from the underlying physical computer infrastructure on which it runs.
This technology has been successfully deployed on mainframes for over three decades, but has only recently been deployed commercially on the now prevalent Intel servers running Windows and Linux operating systems.
Already, it is having a dramatic effect. The technology enables administrators to rapidly create multiple operating systems and server ‘instances' on one or more machines with ease, and to manage these instances from a central point. And because most servers run at a fraction of their capacity, it is usually possible to run several – sometimes even dozens – of operating systems instances on a single server.
Alstom decided to try out virtualisation as part of an overall push to deliver its IT services more efficiently. The Alstom IT Centre operates as a business unit, offering a catalogue of services ranging from the management of 45,000 desktops to supporting multiple intranets and delivering business applications. But all these services are benchmarked against outside suppliers, so it was incentivised to reduce its costs and improve its services.
The cost reduction process involved standardising, where possible, on desktops (Dell, Microsoft Office and Lotus Notes), servers (mostly HP) and storage (EMC Clarion) systems. It also involved consolidating as many servers as possible.
Alstom began to try out virtualisation as a part of this server consolidation process towards the end of 2002, and found the exercise worked so well that over the subsequent two and half years the approach has been rolled out rapidly across its European data centres, in the UK, Germany and Switzerland.
Like most of the early adopters of this technology, Alstom chose ESX and GSX virtualisation software from VMware, a subsidiary of EMC.
Unlike some other solutions, VMware is a ‘bare metal' virtualisation system – the entire software stack, including the operating system, runs on top of VMware, which deals directly with the underlying hardware and peripherals. The technology has been compared to VM, the IBM mainframe operating system that has been used for this purpose since the 1970s.
From the outset, it was clear that consolidation would play a key role. Alstom had some 650 to 700 Intel servers, and a further 150 Unix and other specialist servers. Part of the strategy has been to reduce the number of Intel servers, increase utilisation, and manage them all more effectively.
So far, 30 servers have been set up to run nearly 280 virtual machines, each of which can be provisioned and managed using VMware's VirtualCenter and VMotion system management products. Alstom's Rob Jones estimates that, in the UK, the company has cut its annual operating costs (for delivering an IT service) by up to 40%, through improved management and fewer new servers.
Server utilisation is now running at 50% to 60% and may eventually to get to 80% – extremely high levels for Wintel servers.
The cost improvements – and the high service availability figures of 99.5% – have helped to win customer acceptance. "We have tried to get people away from thinking they own a server. We've been quite successful at this," says Jones.
Provisioning new services is proving so easy – and fast – that Alstom is now trying to reduce the number of instances its administrators have created. "Because the virtual environment is so easy, you must not keep creating new instances of the operating systems, because that can push up the cost of administration," comments Jones.
In spite of all the talk of grids, utility computing and virtualisation in the industry, however, it is not just the end users who need educating. Jones says that he has had problems persuading both Oracle and SAP to support certain virtualised configurations of their software; IBM, along with smaller software suppliers, however, has proved much more flexible.
And what of that other much-hyped component of the virtualised data centre, the blade server? "We don't use them," says Jones. "We're not short of data centre space."