SAN Size Fits AllBy David F. Carr | Posted 2008-01-09 Email Print
How Real-World Numbers Make the Case for SSDs in the Data Center
National print group would lose out on a lucrative contract if it couldn't guarantee a minimum level of storage. the answer: fake it through virtualization.The only thing better than saving money with a new, improved technology is using that technology to win new business.
National Print Group CIO Mike Miller says his choice of a storage area networking system with virtual storage features proved just that pivotal when the Chattanooga, Tenn.-based specialty printer of in-store and outdoor signage was trying to ink an important contract last year. He's convinced he would not have been able to assemble the winning bid if he hadn't figured out a way to significantly lower the cost and boost the efficiency of his storage systems.
"We were approached by a big retailer, one of the biggest," Miller says. "I can't tell you how many millions of dollars this deal was, but it was significant." The twist was that the retailer was asking bidders to bundle a digital content management service into the deal along with their printing services.
To put together a competitive proposal, NPG had to determine the most cost-effective means of storing terabytes of digitized artwork for future advertising campaigns. NPG had a long history of providing value-added services, in addition to more commoditized printing services, but the additional services were typically things like "kit packing"bundling signs and associated hardware for easy assembly by store employees.
"This was a new thing for us, but it wasn't outside the reasonable range of services for us to provide," Miller says. "The only thing was, our total storage capacity at that point was about two terabytes, and this customer needed a minimum of two terabytes to start, plus some service-level requirements we couldn't handle in our current environment."
How could he grow his storage capacity that rapidly without inflating his costs and his company's bid on the contract? He cheated.
Miller chose a storage area network (SAN) from Compellent Technologies that let him allocate more disk space than he actually had installed on his network, through a technique known as "thin provisioning." This storage virtualization approach separates the logical allocation of storage capacity from the physical provisioning of disk storage devices. Instead of creating conventional storage volumes assigned to specific disks, which can lead to wasted space if capacity requirements are estimated too conservatively, Compellent's Storage Center SAN lets storage administrators allocate space generously but only install physical disk capacity as needed.
"It meant I could provide two terabytes of allocated space without immediately purchasing two terabytes of disk," Miller says. The system went live in April, but as of November was still working its way up to that requirement, he says, "so I was able to defer the capital expense for a good six to nine months." He estimates NPG saved $15,000 to $20,000 in disk costs in the first three months alone. In addition, he considered hiring a SAN administrator to support the expansion at a cost of $70,000 to $80,000 a year, but the Compellent solution was simple enough that he was able to make its administration a part-time responsibility for his director of system and network engineering, Dale Rutherford.
Rutherford, who had worked with EMC storage equipment at a previous job, says he has found the Compellent system easy to administer and maintain. "It lets you spend your time thinking about how you're going to use it, not how you're going to do it," he says.
In addition to building the new digital content system on Compellent, NPG decided to migrate off its existing Xiotech SAN. Both Compellent and Xiotech target midmarket enterprises, and both, not coincidentally, are based in Eden Prairie, Minn. (Compellent was founded by former Xiotech executives).
In addition to thin provisioning, the Compellent SAN includes a feature for automatically moving data between different storage tiers, so the fastest and most expensive storage devices are reserved for the most frequently accessed data.
Ryan Walters of Philotek, a reseller that assisted with the NPG implementation, says he made use of the automated tiering by migrating data initially onto the cheapest storage tier, based on Serial Advanced Technology Attachment (SATA) disks, and letting the system decide which data should be promoted to the faster but costlier Fibre Channel segment of the SAN.
"The system recognized, hey, these files are moved a lot, so let's push them up," Walters says. The beauty of the system is that it can make these prioritization decisions at the level of relatively small blocks of data rather than entire applications. For example, e-mail requires fast access, but only for the most current messages. "About 80 percent of e-mail, once it's looked at the first time, is never touched again, so that older e-mail can be moved off to the archive drives," Walters explains.
Miller appreciates that Compellent includes thin provisioning, data tiering and replication in its product, whereas other SAN vendors treat them as add-ons, he says.
Replication in particular would have been a significant additional cost with some other products, and Compellent's replication technology proved better for NPG's purposes anyway because it worked efficiently over the company's existing network and didn't require an upgrade to fiber optics. He estimates moving to a fiber optic network would have cost another $3,500 per monthmaybe more.
Tony Asaro, a storage analyst with the research firm Enterprise Strategy Group, agrees that Compellent's all-in-one bundling is a differentiator. "The only pushback is that some customers may ask, 'If I don't want to use that stuff, why am I paying for it?'
Compellent is one of a handful of startup vendors offering a "highly virtualized" form of storage in which data is spread evenly or "striped" across a large number of disks in a way that adds to the resiliency and flexibility of their systems, Asaro says. Another vendor in this category, 3Par, has been instrumental in helping MySpace.com support the rapid growth of its storage requirements. Most conventional storage systems from EMC and other vendors "don't have this level of virtualization" and are unlikely to be able to retrofit it onto their existing products, Asaro says, while Compellent is offering leading-edge features in a product priced for midmarket customers.
Offering the digital content management service took NPG into uncharted territory, because it had to agree to let outsidersincluding its competitorsaccess the system to download artwork for their own projects for the retailer. Yet Miller thinks NPG has captured the strategic high ground by winning the project bid and serving as the contractor who manages that data.
"We priced it in such a way as to just cover our costs, but now that we have it, it's a barrier to entry for other competitors," Miller says. "Large-format printing is becoming commoditized, so adding data management services is a way to distinguish ourselves." Still, he doesn't want to go overboard by marketing it as a separate service.
"We're not at the point where we're going to say we're a data services provider, not a printer," Miller says.