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Increased demand for storage
Buckeye Color Labs Inc., in North Canton, OH, turned to IP and network-attached storage (NAS) when it faced a sudden demand for storage. The company processes photos. Two years ago, approximately 5% of its customers wanted electronic digital images of their photos. Each image required approximately 30MB of file storage. When the company was handling a few hundred images a week, the storage was manageable. But suddenly, demand for digital photos exploded, and within 18 months, the company found itself processing 6,000 images each week.
Buckeye had been buying IBM servers with attached storage. "We ended up with 14 or 15 servers, which started to get very expensive," recalls Buckeye COO Bob Hendrickson. Adding to the cost was the expense of managing storage on 15 different servers and backing them up. After looking at a large EMC FC SAN solution, Buckeye called in a storage consultant, OH-based Chi Corp., to come up with a less costly solution.
|Pros and cons of IP and FC|
Chi proposed an IP storage network connecting the Buckeye servers with 2.5TB of NAS storage. The company pulled disk drives from the attached storage to help fill up the Nexsan NAS disk arrays and purchased copper NIC cards, rather than more costly host bus adapters (HBAs) to connect the servers. An IP switch from Extreme Networks gave the solution extra ports to accommodate growth. It also added the FalconStor storage appliance to allocate the storage, handle LUN masking and zoning and provide file-level and block-level storage services, says John Thome Sr., Chi chairman.
"We could have done it with EMC, but the cost would be $300,000 to $400,000," Hendrickson says. "What we did cost less than $100,000." The lower cost results in part from Nexsan's use of ATA drives, which aren't comparable in performance to the more costly EMC drives.
TCP/IP offload engine
Although IP is gaining momentum as a way to consolidate storage and to back up storage over distance, it still has some hurdles to overcome, beginning with performance. TCP/IP is a processing-intensive protocol. When used in an enterprise storage situation, it can bring a system nearly to a halt. The solution, suggests David Hill, VP of storage research at Aberdeen Group, Boston, is to offload the processing to a separate processor, in this case a TCP/IP offload engine (TOE). "Offload engines are just starting to arrive," he says. He expects they will quickly become faster and cheaper.
However, you don't need a TOE or even an iSCSI card to create an IP-based SAN. "All you need is an Ethernet NIC and a server running the iSCSI protocol," IDC's Villars says. Windows Server 2003, for instance, will have the iSCSI protocol built in.
Other hurdles involve the immaturity of IP when used for storage. The iSCSI spec was only recently ratified, and products are just beginning to appear. Similarly, 10Gb Ethernet--the desired speed for enterprise storage--is new and still pricey, but products already are shipping. The FC counterpart, 10Gb FC, remains on the drawing board and when it comes it won't be compatible with today's slower FC. In the interim, 4Gb FC--which is slower, but compatible--is on the way.
These hurdles should be surmounted within 18 to 24 months. Vendors are rushing IP and iSCSI products to market. "In another 18 months, you'll have the basic management tools," says Taneja, who expects TOE capabilities to be built into NICs.
But despite the growing interest in IP for storage, industry observers expect FC to remain dominant in the large enterprise. "FC isn't going away, because it is always going to be on the back end," the final link that connects the storage devices themselves, says Don Mead, a member of the SNIA IP Storage Forum governing board and a manager at FalconStor.
But IP storage will continue to grow, says Mead, particularly among small and midsized organizations and for connecting SANs and storage over distance. So, get ready for a dual IP-FC storage world in which FC reigns in the data center, while small and midsized organizations and anyone who wants to run storage over long distances turns to IP.
This was first published in July 2003