Don't Cut CornersBy David Strom | Posted 2011-07-28 Email Print
Best practices for managing storage area networks include developing a disaster recovery program and implementing storage virtualization, tiers and clustering options.
• Don’t cut corners. In the City of Altamonte Springs, Fla., Lawrence DiGioia, information services director, runs twin Xiotech SANs with 50TB of storage in each. To provide additional protection to systems from hurricanes and other storms, the city renovated a 770,000-gallon ground-level water tank with eight inches of reinforced concrete, and integrated it into the main data center.
“It was very cost-effective and green too,” DiGioia says. “The biggest mistake I’ve seen is that people get disappointed in a SAN’s performance because they cut corners, didn’t invest in training, or didn’t bring all their business partners together in one room to plan out their infrastructure to ensure success. Spend the money up front, do proper planning, engage your business partners and provide some training.”
This is especially the case for buying the right amount of backup. “Recovery-time objective is just as important as recovery-point objective,” says Strand’s Bell. “It doesn’t matter if you have up-to-the-minute backups if it’s going to take you a week to restore them. If you have a second backup copy on-site, you can be back online in a couple of minutes.”
Bell learned that the hard way several years ago when a hardware failure took a server down for several hours.
• Flash the cache. Solid-state drives have come into favor for applications in which performance is more important than cost. Storage vendors are looking at ways to marry the high performance of solid-data memory with the lower cost of rotating media to provide the best possible storage solutions.
Vendors include EMC Fast, FusionIO, Viking, Violin and WhipTail Technologies. EMC has shipped some 14 petabytes (that’s 14,000 TB) of solid-state arrays on its own. A solid-state solution is often part of a collection of tiered storage devices, whereby information can move from one device to faster rotating drives on a SAN to slower near-line drives for backup.
“Hybrid solid-state/rotating disk solutions are inevitable,” says DiGioia of Altamonte Springs. “We are looking [forward] to virtualizing and booting our desktops from the SAN.”
• Toss tapes. Given the continuing price decreases for disk storage, tapes don’t make much sense. “Tape management is obsolete,” says Ravi Sachidanandam, an assistant professor with the Mt. Sinai School of Medicine, in New York City. He has several hundred terabytes of SAN storage to handle a variety of advanced medical applications, such as gene-sequencing machines.
“Each week, these alone generate a terabyte of data, and they are running constantly,” says Sachidanandam. “When we last got some quotes for tape solutions, they cost almost as much as hard drives, so it didn’t make any sense.”
“Get rid of tape,” advises Utah Education Network’s Peterson. “We have gone completely to disk, even for backups. The hassle factor of tapes isn’t worth it. Virtualize your backups and use real disks. While the capital costs are initially hard to swallow, the disk backups really perform, and with dedupe, this setup can bring costs way down.”
Altamonte Springs’ DiGioia agrees: “Tape is cheaper, but it’s only 70 percent as reliable as disk backups. Disk-to-disk might cost more money initially, but consider the value of the data you’re backing up.”