Jeff Pieper's marketing design business runs on data, and he doesn't mind swapping out a server or fiddling with cabling here and there. But spending 45 minutes a day moving, compressing, decompressing and deleting files just so his 21-person staff could do their work was too much for Pieper, president of Pieper and Associates.
Rather than buy more servers and network- attached storage (NAS) appliances as his workload grew, he bought a Hitachi Data Systems Plug-and-Play SAN Kit with 4TB of capacity. At about twice the price of a server, it seemed like an expensive risk. "Nobody our size has anything like this," Pieper says. "Everybody was just getting another NAS and another NAS" appliance as their needs grew.
But a year later, Pieper says, the Fibre Channel SAN has more than paid for itself by letting him spend more time closing new business and less time - now only about two hours a month - fiddling with storage.
Pieper's story is typical of small and midsize businesses. Customers and industry analysts say the new, comparatively low-priced SANs - many bundled with preconfigured switches and host bus adapters - are easy to install and can cut management costs by up to 70% compared with storage directly attached to each server.
But they're not for everyone. Low-end SANs often lack strong encryption, continuous data protection, and local and remote replication - features that may be required by businesses in heavily regulated industries, such as financial services. Such features are available in some vendors' "simple SANs", but they may boost the cost beyond what a midsize company can afford, according to Tom Trainer, an analyst at research firm Evaluator Group.
Keeping it simple
These simple, or plug-and-play, SANs use either the Fibre Channel or iSCSI protocol, although low-end iSCSI SANs have received more attention because of their affordability. Internet SCSI allows the SCSI commands needed to communicate with Fibre Channel drives to be transmitted over Ethernet. This reduces hardware costs, since most offices have Ethernet networks.
The iSCSI SAN hardware costs 20% to 40% less than comparable Fibre Channel hardware, but both types of simple SAN reduce administrative costs with easy-to-use software that automatically creates and resizes volumes, migrates and compresses data and moves data among volumes and arrays as needed.
Among the major iSCSI SAN vendors are LeftHand Networks, EqualLogic, Network Appliance, Intransa, EMC and Dell. Vendors on the Fibre Channel side include EMC and Hewlett-Packard.
Many low-end SANs are deployed to move companies away from disk drives directly attached to servers and to store bulky files generated by Microsoft Exchange e-mail servers. When the Jefferson Union High School District in California relied on direct- attached storage (DAS), it had to impose strict quotas on the e-mails and files that teachers and students stored on the network servers. But since installing Hitachi's Plug-and-Play SAN Kit with 8TB of storage, the district has encouraged students to post portfolios of their work online, says Lou Silberman, technical director of the school district.Software vendor Quark purchased two 6TB Network Storage Module (NSM) arrays from LeftHand Networks about a year ago to store Exchange data, user files and software source code, says Mark Lawler, vice president of IT. He says he chose NSM for its ease of use and because it cost less than rival products from EMC and Network Appliance.
Although Lawler and his staff had to create volumes and authentication groups - "normal tasks you have to do with any SAN or NAS" - and had "never seen a LeftHand product before," they had the SAN up in two days, he says. Lawler estimates that his SAN has cut his storage management costs by 70% compared with the previous DAS system.
Hitachi installed the SAN for Silberman, but his staff was able to use the management software to reconfigure the array with only 30 minutes of training. He estimates that his staffers spend 20% to 30% less time managing the storage than they did before.Several SAN customers also praised the ease of adding more storage to iSCSI SANs. Pieper, for example, says that if his current SAN runs out of space, "all I have to do is get another box and plug it in the back, and it keeps on going."
The Ethernet networks used by iSCSI SANs are slower than Fibre Channel, since they top out at 1Gbit/sec., compared with 4Gbit/sec. for the latest Fibre Channel hardware. But the performance gained by moving to a SAN from direct-attached storage is so great that many midsize businesses don't miss the speed of Fibre Channel.
However, data warehouses or multi¬media applications could slow down Ethernet networks because they move large blocks of data at the same time, Trainer says. For such applications, consider Fibre Channel SANs or at least putting the iSCSI SAN on a separate network segment.
Greg Schulz, an analyst at The StorageIO Group, questions whether the graphical management tools so useful for today's comparatively small SANs will still be effective "when you have to install 200 or 500 ports on a server."
Gartner analyst Roger Cox recommends that small and midsize businesses equip their servers with dual host bus adapters or interface cards, as well as dual switches and storage controllers, to ensure uptime if one fails.
Finally, analysts say, be sure your low-end SAN vendor provides virtualization capabilities that make it easy to combine your various physical SANs into one virtual pool of storage as your storage volume grows.
For many midsize companies still looking to move off of DAS, these concerns are down the road while the benefits are immediate. As Silberman says, "It's a great relief to get this massive amount of storage, at this kind of price and this kind of easy functionality."