Here's what you need to tell your customers
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Storage-area networks (SANs) are evolving like a new bridge under construction. The span is ready for traffic, but the roads that feed into it are still being built. Ultimately, many thoroughfares will lead to that bridge. The choice involves which way to go.
Glossary of Storage Terms
Not long ago, only the largest of enterprises were deploying SANs, primarily to bridge the storage of large, mission-critical systems that were generating massive amounts of transaction-oriented data. But now, the role of SANs is actively expanding from storage networks centered around homogenous systems or applications into core components of enterprise systems. Thanks to the availability of entry-level SANs and some improvements in interoperability, SANs today represent one of the largest growth opportunities for solution providers offering system, network and storage-integration services.
"Companies are going beyond the island concept and starting to look at the bigger picture. [They're starting to put in storage as more of a utility that's going to be shared among multiple projects or by multiple departments," says Richard Baldwin, president and CEO of Nth Generation Computing, a solution provider based in San Diego.
In recent months, the argument that network-attached storage (NAS) is specifically reserved for file-level data such as e-mail and documents, and SANs are only for block-level, transaction-oriented records, has shifted. True, that basic premise still holds, but SANs are now evolving into the bridge that connects all enterprise storage, including NAS, direct-attached storage (DAS) and even tape repositories.
"I'm seeing customers who were emotionally vested in NAS technology beginning to recognize it is not the panacea," says Bill Oliver, an operations director at PDC Solutions, a storage integrator based in King of Prussia, Pa.
That's because the proliferation of DAS and NAS servers, often increasing at rates of 50 percent each year, has become a management headache. Another factor is the recent release of lower-cost, entry-level SANs. Those include Cisco's SN 5428 Storage Router, HP/Compaq's StorageWorks NAS S1000 and QLogic's SAN Connectivity Kit, all of which cost less than $10,000 and include an eight-port switch, host-bus adapters (HBAs), fiber optic cables and connectors, and management software. These systems let businesses consolidate data from different server platforms, such as Windows and Unix, onto common storage systems,an unthinkable prospect, until recently.
"With many of our clients, we see one group that handles the Windows environment and another group that handles Unix, and they generally won't let one group touch the other's hardware. But those barriers are starting to break down," Baldwin says. "We are now seeing more companies recognize that they should pick a standard for storage,be it Compaq, EMC or Hitachi,and then start connecting all the different groups into a shared-frame type of environment."
For years, many companies resisted SANs because its hardware costs were higher than other storage methods, and because SAN architectures were overkill for anything other than mission-critical applications, such as databases or ERP systems. Besides shipping with only high-end switches, which could have anywhere from 64 to hundreds of ports, SANs could be connected only with dedicated fiber optic cable,overkill for workgroup systems. But with support for various new IP-based protocols,such as Internet SCSI (iSCSI) and Fibre Channel-Over-IP (FCIP) (see "Glossary of Storage Terms" on page 54),early adapters are now implementing SANs over fiber, but they are bridging SANs and other storage systems via WANs to remote locations.
Two key business requirements have been coinciding with this shift, in addition to a bevy of new products that are enabling broader SAN connectivity. One is the realization that, in the wake of last fall's terrorist attacks, many companies need to assure their corporate boards of directors, shareholders, customers and partners that they'll be able to maintain business continuity even if a disaster strikes a location where data is stored. That means data can't just be archived, and it has to be brought back within hours,if not minutes.
The other reality is cuts in IT budgets are forcing data-center managers to reduce the cost of managing storage. By some accounts, anywhere from 30 percent to 70 percent of storage capacity on servers, NAS and archival media goes unused because disks are scattered all over an enterprise. If storage were networked, not only could capacity be better used, but companies would not have to dedicate as many administrators to manage it. In fact, observers say hardware only represents 20 percent of the cost of managing storage.
"Companies have had to reduce head count, so they need architectures that are less people-intensive and more manageable," says Barb Miller, director of technical services at Tech Data, Clearwater, Fla.
According to Robert Passmore, a Gartner research director, large enterprises that have implemented SANs are seeing three to 10 times productivity improvement in their IT organizations. More than 50 percent of all storage systems are now networked,up from 23 percent a year ago, he says,and by 2005, 90 percent of all storage will be networked.
That's good news for solution providers. While sales of NAS solutions through indirect channels will reach a healthy 30 percent of an overall worldwide revenue of $2.5 billion, SAN sales through the channel will reach 40 percent of an overall revenue forecast of $6.5 billion, according to researcher IDC.
"Solution providers with expertise in storage are in a good position,everybody wants them," says IDC analyst Janet Waxman.
But because of the diversity in system and network environments, observers say it's important for solution providers to forge partnerships with a broad but manageable number of vendors.
"Customers need someone to take a neutral, third-party, unbiased approach in architecting a solution," says Vito Valenzano, director of storage practice at Comark, a solution provider in Bloomingdale, Ill.
Sometimes that means resisting the temptation to recommend implementations of specific preferred suppliers.
"There's a tendency for vendors to encourage a one-stop shop," PDC's Oliver says. "While from a maintenance and support perspective that's a good idea, the technology has become so disparate from one storage vendor to another it seems unlikely that one can do it all well."
For example, while PDC bills itself
as a Sun partner, if a prospect is looking for a storage solution centered around Microsoft Exchange, Oliver is likely to recommend HP/Compaq's products,
Solution providers should also be prepared to discuss the basics with customers; many have questions about whether to build a SAN, whose components to use and how to implement these different solutions.
"I have customers who don't know the difference between NAS and SANs,or that there even is a difference," says Denise Buonaiuto, IBM's vice president of worldwide partner sales.
Even customers with expertise in storage are struggling with the various approaches to implementing SANs, says Dianne McAdam, an analyst at Illuminata, a Nashua, N.H.-based consulting firm that specializes in large-scale enterprise computing. "Customers have a lot of options now," she says. "There's some confusion over that."
Those options include traditional Fibre Channel, which supports up to 1-Gb speeds; 2-Gb products; IP-based options that are also starting to ship; and, in several years, systems that support 10-Gb speeds, both via IP and fiber. Then there are standards that could become a factor in years to come, such as Infiniband, which is intended as a new server and cluster interconnect.
"You can do whatever you want today, but you will replace it in 2004," as needs for higher-speed connectivity dictate, says Gartner's Passmore, though he thinks Fibre Channel will remain the dominant SAN interconnect standard.
Despite improvements in interoperability among SAN switches, whether one vendor's product will work with another's is still somewhat of a crapshoot. For example, not all leading SAN switches can share data, Nth Generation's Baldwin says.
"To be very candid, it is still a problem," he says, noting that Brocade Communications Systems' SilkWorm fabric switch doesn't link to McData's Director switch. While many storage vendors offer both, "they offer them in isolation," Baldwin says. "You pick what's best for your environment, and you have to stick with it."
To ensure interoperability, first-time SAN buyers tend to purchase from a
single vendor, but a growing number of customers are starting to add different vendors' wares to their systems, says Kevin Schoonover, director of engineering at Arrow Electronics, Melville, N.Y. "Interoperability is required to maintain their existing investments and give them the flexibility to scale without replacing existing hardware," he says.
But PDC's Oliver says, for the most part, he has not encountered interoperability problems at the switch level.
"With the new switches and HBAs from Brocade, QLogic and a few others, those packets are translated on-the-fly at the switch level," Oliver says. "What that means is my Sun box can be configured to see the storage attached to my Compaq system. There's been effectively a hardware and software breakthrough in the way packets are dealt with at the switch," he says, referring to port-level translation utilities.
For those looking to bridge their SANs beyond the Fibre Channel network, IP is starting to gain acceptability, albeit incrementally, and opinions vary widely on the best way to connect data. In just the past two months, several vendors, including Cisco and IBM, have started shipping appliances that link Fibre Channel SANs to remote locations.
"The problem with fiber [optics is it's fragile,it's glass, it breaks and it's expensive," Oliver says. "And it's a dedicated cabling system." The downside to IP, however, is it's only capable of half the speed, and it's not as reliable as fiber, he explains.
Plenty of products that support methods of connecting data over IP are available, such as iSCSI. Cisco's new SN 5428 eight-port Fibre Channel switch has two iSCSI ports, as well as blade products that support its Catalyst 6000 chassis. IBM is now shipping its IP Storage 200i, an appliance that can be connected between a SAN and any Ethernet LAN.
Critics argue the release of iSCSI products is premature because the standard has yet to be finalized.
"You've got to separate hype from reality,sometime later this year, SCSI-over- IP will just start to become viable," Comark's Valenzano says.
Scott Drummond, an IBM program director for storage networking, counters that if any of the iSCSI specs change, it would only require a microcode upgrade through firmware.
"True, the standard is not complete, but it's one of the fastest-moving standards that has ever gone through the Internet Engineering Task Force because of the cooperation and momentum behind it," adds Nancy Marrone, an analyst for consultancy Enterprise Storage Group.
Despite the posturing, customers are starting to deploy iSCSI anyway. Baldwin says Nth Generation has installed several iSCSI-based solutions, such as at San Diego Children's Hospital, to augment storage for its file-and-print servers, rather than having to add more drive slots or more direct storage. "It's not vaporware,it's there, and it works," Baldwin says.
Other approaches that involve Fibre Channel protocols to connect SANs over IP networks include new FCIP solutions, which tunnel SAN packets over IP, and iFCP, which converts FCP packets so they can run over TCP/IP and Gigabit Ethernet networks.
Still, experts insist vendors' claims of standards support are fine, but solution providers need to assure customers that products will interoperate. They should test interoperability for themselves.
Larger solution providers are installing their own labs. Comark, for example, has a lab with $4 million worth of equipment. IBM is currently rolling out test labs throughout the world. Its Total Solution Centers are open for providers to run their own compatibility checks. Tech Data has its own test center, and the Storage Networking Industry Association has a huge interoperability lab in Colorado Springs, Colo.
"It is our hope that industry organizations...can help vendors maintain their edge of features and function while maintaining interoperability," Arrow's Schoonover says.
Use of those or other labs is critical, observers agree. "SANs have come a long way, but I think there is still a great need to verify interoperability," Marrone says. "If I were [the integrator, I'd make sure I tested it before I installed it."