Consolidation leads to a new Dimension

A major server virtualisation exercise is the latest in a string of infrastructure changes that has seen Dimension Data, a nationwide voice and information systems integrator, consolidate 22 offices into 15 and centralise its voice, storage, and server architectures into a single Sydney data centre.

That's a big ask for any company, but the high-profile integrator -- whose business depends on its ability to help customers toe the line between bleeding-edge technology and carefully managed risk -- faced additional pressure both to apply its own best-known practices, and for the technology migration to succeed on the first go. A high-profile failure, after all, could damage the company's reputation for technical excellence.

"Being a systems integrator, we need to be in a position to advise our clients about this technology, and we see the best way to do that is to demonstrate that and experience it through our own use," says CIO Paul Christensen. "That's a very difficult question from an IT management perspective: we're very driven to run new technologies as they come out, but there's also a degree of reliability and availability you need to build into the environment."

Having toed the conservative line for years, plans for a full technology review had been gradually evolving ever since the company (previously Com Tech Communications) began charting a path in the wake of the 2001 rebranding by its current South African parent. Even then, the initiative to take stock of its internal operations revealed the company's office network was riddled with redundant and disorganised technologies.

"We had grown over time, a lot of our infrastructure was decentralised and each office had a range of services where there was a fair bit of duplication," says Christensen. "Each was managed locally, and in many instances in a somewhat haphazard fashion because we have people that were focused on revenue-generating activities, but also sharing responsibility for the internal infrastructure. There were some fairly significant opportunities for consolidation, reducing superfluous costs and improving the overall manageability of the environment."

Three steps, one long journey
Centralising data stores was an obvious way to improve the consistency of data between offices, but the company didn't stop there. Strategic planners laid out a long-term IT blueprint, comprising three staggered phases, that was intended to both modernise the company and trim redundancy.

The first phase focused on consolidating services and infrastructure at an office level; the second focused on optimisation of telecommunications services. The third phase involved standardisation of the company's data centre infrastructure, which has exploded in recent years as the firm moved to complement its internal systems with gear for providing managed services to external customers.

After a comprehensive business process review identified the best candidates for consolidation, the company was able to merge 22 Dimension Data offices into just 15 locations. In contrast to its original product-focused structure, these offices were realigned along functional roles -- in keeping with the company's ever expanding range of consulting and managed services.

Rationalising its branch office network also gave Dimension Data the opportunity to review its telecommunications infrastructure. A review of installed wide area network (WAN) connections identified many poorly utilised and unduly expensive services that had persisted over time but did not need to be retained. It also became clear that six previously separate PABX phone systems were hindering efforts to manage employee communications services across the country.

"We looked at the way we had grown somewhat haphazardly over a period of time," says Christensen. "The main focus was to consolidate those services where possible to ensure that we had the correct mix of services for the organisation's need -- and to make sure we didn't have any services in place that were adding costs to the baseline and adding very little value."

Voice over IP (VoIP) was the major new technology introduced during the second phase, with Dimension Data rolling it out across its business in a push to cut telecommunications costs and simplify management of the large calling environment. The shift went smoothly, with a complete upgrade facilitated by the introduction of Cisco Systems VoIP handsets throughout the company's branch offices.

Major benefits came after Dimension Data implemented its VoIP environment around a single centralised server running Cisco's Distributed Call Manager (DCM). Compared with the previous fragmented PABX environment, the single DCM server made it far easier to track user authentication, profiles, and other maintenance tasks that had been complicated and expensive in the previous environment.

Overall, the company's telecommunications reshuffle slashed its voice and data expenses by more than 40 percent. "Having a centralised [DCM] cluster increased our levels of redundancy, levels of control, and simplified the management process in terms of provisioning of users and services, our ability to upgrade, and so on," Christensen explains.

Into the virtual Dimension
Because its business depends on guiding customers into new technologies, Dimension Data had for many years seen the value of both consolidation and virtualisation, which provides a greater degree of IT flexibility by creating layers of abstraction between hardware, software and network services.

The gap between the company's ambitions and the capabilities of nascent virtualisation technology, however, initially prevented it from pursuing this goal. It was only last September that Dimension Data was able to begin what would become the most complex part of its infrastructure refresh: the shift from a broad range of operating environments to a single, standard clustered server environment based on Microsoft Windows 2003 Server.

With more than 150 servers installed across 25 racks in the company's data centre, managing the facilities had become extremely expensive: Christensen estimates a cost of around $20,000 in annual maintenance for each of the servers the company was using. Consolidation was more than an academic exercise, however: the data centre was drawing so much power that the company had had to divert power meant for other floors of its building.

"Because we had added so much computing power into the facility, it had overloaded the building supply," says Christensen. "The building water supply couldn't support our running our two air conditioning systems full time, and we had also reached floor weight limits in the facilities. When you're in those sorts of situations and building management can't offer a service level around the fundamental requirements of the centre, you have to start to re-evaluate the situation."

Reducing the number of servers within the facility slashed the overall power draw, allowing the company to scale and reconfigure its server infrastructure using virtual rather than real, power-drawing servers. Utilising VMWare ESX Server virtualisation technology, Dimension Data now hosts more than 200 virtual servers on an array of just two dozen physical boxes, including IBM xSeries 366 rack servers and BladeCenter HS20 blade servers.

Space to grow
To complete its data centre reinvention, Dimension Data also consolidated its data storage, which had previously been what Christensen calls "predominantly captive [server-attached] storage with utilisation levels as low as 10 percent".

Although the company had a small storage area network (SAN) in place, the addition of numerous EMC CX500 storage arrays raised the SAN's total capacity to 12 terabytes and offered the promise of additional growth as the company continues to grow. Storage, too, is virtualised to smooth accessibility by all manner of applications and operating environments.

It has taken some time, but Dimension Data's data centre spring clean has completely restructured every aspect of its IT infrastructure. Weight, power and water considerations have been resolved; manageability has improved; scads of centralised storage have facilitated backup and hinted at future capabilities; and server virtualisation has slashed maintenance costs and ensured that the company's data centre will continue to support its expanding business requirements for the long term.

"We've created some real cost benefits across the infrastructure, and it provides a much greater level of flexibility in terms of the way we manage the environment," says Christensen. "Through this process we have managed to unlock a lot of the potential within the infrastructure that we hadn't been able to make use of before -- but this was always a journey that we saw taking us some time. Over time, we'll be focusing on really making our assets sweat a bit more."