By Sonia R. Lelii
The rapid proliferation of NAS devices over the last several years has led to management problems. For example, poor utilization and an inability to manage load balancing among devices have become common. "End users are beginning to find out that there can be too much of a good thing," says Bob Nusbaum, senior product manager at NeoPath.
NeoPath is the latest among a handful of vendors-including Acopia, NuView, Rainfinity, and zForce-that have jumped into an emerging market sometimes referred to as file virtualization or what one analyst firm, the Taneja Group, calls network file management (NFM). NFM solutions are designed to alleviate the management headaches associated with the rapid growth of NAS servers. (For a complete report on NFM, see "Network file management solves NAS problems," InfoStor, October 2004, p. 34.)
This month, start-up NeoPath introduced an appliance solution, called File Director, that enables users to more easily load balance among NAS devices and file servers, improve performance, and consolidate devices.
In October, Rainfinity released its RainStorage version 3.0 with specific application modules to enable tiered storage management, performance optimization, capacity management, file server consolidation, and disaster-recovery capabilities.
While all of the NFM vendors compete, they have different approaches. For example, Acopia and NeoPath address load balancing and data migration and also focus on creating a global name space, according to Arun Taneja, founder of the Taneja Group (www.tanejagroup.com).
The idea behind a global name space is to take numerous individual file systems and create a single file image, essentially consolidating disparate file systems. Appliances from vendors such as Acopia and NeoPath sit in front of file servers and are in the data path. NeoPath's Nusbaum claims that one benefit of being in the data path is that the device can accumulate statistics about how the file system is being used.
Through automated policies, the device can categorize files by, for example, size, data type, and time of creation. "We are not just switching file traffic," says Nusbaum. "Administrators can set up a policy to take, say, the top 10% of the most frequently accessed files and move them from a slow server to a higher-performance NAS filer. If the device is not in the data path, it doesn't see that kind of information."
In contrast, Rainfinity's appliance can be positioned either in or out of the data path. Jack Norris, vice president of marketing, says that Rainfinity's solution has three key components: It enables tasks such as performance optimization and disaster-recovery capabilities; it works as a transport protocol switching engine; and, like NuView's product, it is integrated with the industry standard global name space-Microsoft's Windows Distributed File Service (DFS). RainStorage operates as a layer-2 switch with file-system protocol intelligence and is transparent to clients and IP-based storage devices.
The protocol-switching engine enables the system to move in-band when administrators want to do specific tasks. "We don't sit in the data path until you want to do optimization, balance capacity, or create tiered storage. Then we move in-band to solve those issues," says Norris.
Taneja says that there are pluses and minuses with NFM appliances that reside only in the data path. The downside is that it can introduce a potential point of failure. The upside is that the architectures are designed to be scalable.
In general, Taneja says several applications for network file management are gaining traction, including storage consolidation, archiving, data migration, and disaster recovery and business continuity. But users should be cautious because NFM is still in its infancy. "These solutions have not been battle-tested yet," says Taneja.
Sonia R. Lelii is a freelance writer in Framingham, MA.