SAN/NAS Convergence: Moving Toward A Unified Storage Strategy

For more than a year, we have been hearing about the convergence of SAN (storage area network) and NAS (network attached storage) technologies. But are we any closer to seeing the technologies truly integrated?

"We have always believed that SAN and NAS could coexist on the same network," says Akshay Gupta, general manager of the NAS division at Iomega Corp. (San Diego). "But SANs were really built for the data center, whereas NAS is a product more for the small- to medium-sized businesses and work groups of enterprise companies. To move into the data center, NAS has to coexist comfortably with a SAN. SANs are architected into a data center, and NAS is simply plugged in. Therefore, if there is a SAN on the network, the NAS has to be able to play with it because the SAN is an integral part of the network."

Gupta believes most end user companies will eventually need both SAN and NAS. Some applications require file sharing, and in many of those applications, NAS is the best solution. "It makes no sense to use a $500,000 SAN to pull a file off a server; that is like using a howitzer to shoot a mouse," says Gupta. "The two technologies have a place on the network because even in companies that have a SAN, there are some applications where leveraging a SAN to do the work does not make sense."

Should SAN And NAS Converge?
Mark Amelang, director of marketing for Auspex Systems, Inc. (Santa Clara, CA), believes SAN and NAS convergence is really a paradigm shift in the way storage pools are exploited. "In the enterprise space, there were NAS servers that were run by the engineering or technical groups that had the requirement for file sharing," he says. "Enterprise companies also had a SAN, which served block-level storage through application or database servers and were run by the corporate IT guys. We believe there will be a convergence because customers want to store all their data in one storage pool and administer it as one storage pool. They also want reliability and functionality that is standard across the board. To achieve this scenario, the next level of SAN/NAS convergence will involve agents, or functional computing engines, sitting on top of the storage pool serving out SAN functionality on one side and NAS functionality on the other."

The discussion of SAN/NAS convergence centers on simplicity of managing storage. Amelang notes that 500 GB of storage used to be considered a lot of capacity for a NAS server. But today 10 TB is not outrageous, and many companies are going to 100 TB. "The game today has to be about simplicity of storage management," he says. "With 100 TB instead of 500 GB, companies need to manage all of their storage smarter. Administration has to be done on a macro level. That means taking an open systems approach with NAS servers that can sit on top of any vendor's SAN. NAS services can then be offered from the shared storage pool."

Unify SAN And NAS Platforms
Leonard Iventosch, senior director of worldwide channels for Network Appliance (Sunnyvale, CA), believes the solution to SAN/NAS convergence will be a unified platform for both technologies. "Many vendors are now trying to come up with a unified strategy, because they realize VARs need to solve customer problems, not get involved in technology wars," he says. "I think we found ourselves going on a lot of sales calls to prove to our customers that NAS was a better solution than a SAN. Even if you win that argument, it is not a comfortable call to make." With a unified storage strategy, NAS VARs will not have to tackle SAN competitors head-on to win business.

So where does this unified strategy stand? "We are moving toward a unified approach," says Iventosch. "But getting the two technologies to talk to each other is tough, because they do not have common architectures. Another problem is that convergence still means different things to different people. But I believe the time is coming where we will talk about a storage network and not even discuss whether it is NAS or SAN. The distinction will no longer be an issue. Speeds, throughput, and access to blocks of data and files will be seamless and behind the scenes. But that scenario is still a few years away."

Focus On Solutions Currently Available
Reza Sadri, chief technologist for Procom Technology, Inc. (Irvine, CA), agrees with Iventosch. "SAN/NAS convergence is important, but it should not be the most important consideration for VARs and end users," he says. "A lot has been written about SAN/NAS convergence, but most VARs and end users remain confused about whether they can do it. Virtualization offerings are talking about performing that convergence, and while it's a great concept, we are just not there yet and it may be a couple more years before we are."

Sadri believes performance is what is keeping NAS out of certain environments, but as those performance barriers are broken down with new technologies such as iSCSI (Internet small computer system interface), NAS will be able to handle more functionality. There are products on the market right now that allow for SAN and NAS functionality in the same box. These products have a Fibre Channel SAN back end and a NAS filer that is used to serve files. "This enables users to have a SAN environment backing up a NAS box without having to install an entire SAN infrastructure," says Sadri. "That is an appealing solution to resellers because they can add a lot of value. They can also add a backup piece to it, integrate the solution, and perform the database integration. With a versatile NAS box, they can build a lot of solutions and add a lot of value."