Data Centre Design

The cloud may garner many IT headlines today, but many companies still elect to build an in-house data centre. The goal of successfully designing and implementing a data centre on time and within budget is one that many organisations aspire to but few attain. Given the complexity of a typical facility, detailed planning is critical; thus, this series on data centre design will emphasise some of the key considerations and decisions that companies must tackle long before the shovel hits the dirt. The opening foray into this topic focuses on what companies must investigate before pondering such design aspects as tier level, cooling architecture and even site selection.

Data Centre: To Be, or Not to Be?

Even if your company needs only a few servers’ worth of IT capabilities, your choice of whether to go the in-house (data centre) route or to outsource will dramatically affect your finances, control of resources and level of responsibility for various aspects of your systems. In some cases, this choice is simple: security or latency requirements, available capital, company focus and similar factors may immediately dictate that a company-owned data centre is necessary—or out of the question. Is your company ready to design and build your own data centre? Ask yourself tough questions, like the following:

• Can you afford it? The cloud and other outsourcing methods enable you to pay as you go rather than making a large capital outlay. Building a data centre is expensive from the start, and you’ll still incur operating and maintenance expenses throughout its life. If your company coffers are looking meagre, you’ll need to get a loan; are the company finances up to the task?
• Will it be a distraction? Unless you are in the business of offering data centre services, an in-house data centre will likely be a peripheral project relative to your main business focus. Will building and operating such a facility help or hinder you in attaining your business goals?
• Are you willing to troubleshoot problems on your own or with outside help? Everything requires maintenance. Eventually, your data centre will, too—perhaps late at night or at an otherwise inopportune moment. You’ll need either in-house talent to fix the problem or a list of reliable outside help that can jump on the task quickly.
• Do you have a vision for dealing with growth? If your business increases, will you be able to afford commensurate growth in your IT infrastructure? Or will your data centre become an “orphan” because you later decided to pursue the cloud?

Even if you want to run your own IT equipment (servers, storage and so forth), you still have outsourcing options. You might consider colocation, for instance: effectively, you control the IT, and a service provider controls the facilities (cooling, power distribution and backup, security, and so on). The decision to outsource or not is a nuanced matter that, although not the focus of this series, requires its own due consideration. But if you’re set on building and operating your own data centre, the fun is only starting.

Listen to the Money Talk

Naturally, cost will (and should) remain a critical aspect of each design decision. A state-of-the-art 10MW Tier IV data centre might sound great, but if you only need a few low-density server rows and have no strict uptime requirements, the cost of such a facility would far outweigh any potential returns on the investment. To that end, several overarching themes—balanced by cost considerations—should guide the design effort:

• Audience - Know whom you’re designing the facility for and what its mission is. Will the data centre serve just company employees, or will it serve external customers as well? When will users typically access services—just during the workday, or at all hours? Be sure to gain a clear picture of the mission you want your data centre to accomplish.
• Growth strategy - If you have a fixed level of business that you’re sure will remain static over the life of your data centre, you can plan for a fixed architecture. For everyone else, changes in business (growth, or even decline) means that a data centre’s capacity may become inadequate or overkill later on. Your design strategy should therefore take into account reasonable prospects for growth (or the reverse) by, for instance, focusing on modularity.
• Pay now/pay later - Sometimes, making a capital outlay (capex) now can save operational expenses (opex) later. For instance, a newer and more energy-efficient server can cut power consumption (and thus overall cost). On the other hand, a lack of sufficient capital, or some other consideration, may mean that the lower capex/higher opex route is more reasonable. Either way, looking at the total combined expense is critical to cost-effective design decisions.
• Reasonable expectations - If your data centre plan assumes the sum of the lowest estimated costs and the fastest implementation times, you’re almost certain to face crushing disappointment when the inevitable stumble occurs. Although getting a larger budget allocation may be difficult, you’re far more likely to be pleased with the results if the project finishes under budget and ahead of schedule than the alternative.
• Help - Unless you’ve designed data centres in the past, you are probably unaware of many pitfalls that professionals regularly encounter. Hiring design consultants costs money, to be sure, but it can also save many (expensive) hassles in both the short term and long term.

Avoid Green Fatigue

There’s nothing wrong with making a profit: your data centre design decisions should keep profitability as a primary goal. But profitability and environmental stewardship need not be mutually exclusive; in fact, the “greener” route (e.g., energy-efficient servers) is often the more profitable one. In addition, there’s nothing wrong with attempts to strengthen the company image. But don’t go overboard: ensure that your efforts are sustainable over the long term and that progress is the goal. That being said, it’s also important that sometimes a bit of a sacrifice to improve the world we all must share—even if it doesn’t improve your financial stats—is everyone’s responsibility. If we all do a little, we can collectively accomplish much.

Conclusions

The first step of data centre design is to make sure an in-house data centre is the best option for your company. Outsourcing is in many cases a better option, so you should take careful stock of what you need and what you expect from your IT implementation. Once you’re set on building your own facility, you need to prepare an overall strategy before digging into the technical details. That includes recognising the requirements of users, accounting for growth prospects, having reasonable expectations and mile markers, and so on. Subsequent parts of this series will turn to some of the more technical considerations associated with designing your own data centre.