»  Search

Enterprises long ago discovered that decoupling storage from servers makes great sense. Networked storage, such as storage area network (SAN) arrays, is easier to share and expand. And, in many cases, networked arrays are more cost effective than buying and dedicating storage to individual servers.

As a result, SAN storage arrays have become so common that it’s tempting to judge and purchase them like commodities. But there’s more to choosing an array than raw storage capacity and a price tag. Factors such as manageability, adaptability and disk utilisation efficiency are too easily overlooked – and poor performance in these areas can leave businesses with less than they thought they paid for.

Before investing in a SAN storage array, ask these questions to avoid hidden costs and get the most for your money:

• How efficient is disk utilisation?
• How complex is management and administration?
• What about expandability?

Don’t get blindsided by an array that makes inefficient use of storage capacity. According to IT analyst firm Enterprise Strategy Group (ESG), about 30 to 50 percent of array storage is typically stranded and unusable. This idle space is locked to an application that doesn’t need it, rendering the empty space inaccessible to other uses. Some arrays can dramatically reduce that stranded and unusable space, saving money today and in the future.

If you’re not getting efficient use of the available storage in your array, you might be paying more per gigabyte than you thought.

Be sure to understand how the device allocates and reallocates storage resources. Does the storage method maximise the capacity on hand? Can it both shrink and grow storage pools and reassign storage to different applications without going offline?

2. How complex is management and administration?

Management and administration are among the fastest growing costs in IT today and storage administration isn’t exempt from this trend. That’s why easier array management is more than a nicety, it’s a necessity.

Don’t overlook the staff hours (and training) that overly-complex arrays can add to your existing burdens. Some important questions to ask include the following:

• Does the array allow administrators to monitor and control performance, utilisation and reporting from a single view? This aids in faster end-to-end troubleshooting and quicker problem resolution.
• How many steps does it take to accomplish a simple task, such as adding a new disk?
• How many common tasks are automated? The more tasks the array takes care of itself, the less time staff spends “babysitting”.
• Is the interface simple to understand? Could an IT generalist, rather than a storage specialist, administer the array?

When considering a storage array purchase, it’s important to be forward-thinking, yet you don’t want to invest in so much capacity that you can’t take advantage of steadily-falling disk prices.Instead, look for an array that can be configured for near-term needs, yet can easily grow as your storage needs grow. You should be able to add more storage or swap out malfunctioning disks without downing important business applications that rely on the array or manually reconfiguring arcane array settings.

Think outside the array box

So many factors affect the real cost of a storage array that making an investment can seem like a shot in the dark. But stick to a few guidelines – such as disk utilisation, ease of management and flexibility – and your decision will be much clearer.

Not only does HP’s Enterprise Virtual Array, or EVA, use disk space efficiently and scale painlessly, but it’s also supported by a portfolio of hardware, software and services that can further simplify the way you manage your business’ ever-growing storage.

In fact, compared to competing arrays, HP’s EVA can store 30 percent more data with the same amount of disk capacity. When technology research firm Alinean compared the EVA to a competing NetApp array, it found that the EVA offers 34 percent higher disk utilisation.

The EVA’s simplified management streamlines storage maintenance and administration, which can save precious IT personnel hours. Analysis from research and technology firm Edison Group (PDF, 1.13MB) demonstrated that a storage administrator can perform a series of standard tasks in 70 percent fewer steps on an HP EVA than on a similar EMC system, and 82 percent fewer steps than on a similar NetApp system. That means the EVA requires significantly less time to manage, to wit, 79 percent less time than EMC and 76 percent less time than NetApp. The study found that the HP EVA can provide up to five times the management efficiency of EMC and NetApp systems, depending on the operation performed.

In addition, HP tools such as Systems Insight Manager allow administrators – generalists and specialists both – to control and monitor EVAs alongside the rest of the IT infrastructure from a single interface.

Flexibility is one reason the Rhode Island School of Design chose HP StorageWorks EVAs to consolidate and expand storage capacity with ease and economy.

“When we looked at all the options, it became clear that the flexibility and scalability of the HP Enterprise Virtual Array offered a more cost-effective alternative and fit our strategic goals for managing our increasingly critical digital resources,” says Ralph Fasano, associate vice president for the office of information technology at the preeminent art and design college.

The EVA’s simplified management is expected to bring a cumulative five-year benefit of US$275,000 in productivity increases to CitiStreet. One of the largest global benefits delivery firms in the United States, CitiStreet consolidated its storage on EVAs serving Windows file servers, Linux® and some legacy COBOL applications. The EVA’s manageability was a major factor in CitiStreet’s choice: “We needed to find a storage solution that was affordable, could be easily managed, and was easily scalable so that it would meet our constantly growing storage needs,” says Jeff Machols, systems integration manager at CitiStreet.

The EVA’s manageability, adaptability and efficient disk use help take the unpleasant surprises out of buying a networked storage array.