What will the next generation of network-attached storage (NAS) look like?
ExaGrid Systems, Westborough, MA, thinks it knows and is calling it Grid-Protected Storage. An architected solution, Grid-Protected Storage promises to deliver distributed, shareable storage with data protection. It integrates policy-driven backup and restore, disaster recovery, on-site and off-site vaulting and compliance archiving directly into primary storage. The product, according to the company, should result in lower costs and less complex data storage.
Arun Taneja, senior analyst at the Taneja Group, Hopkinton, MA, describes Grid-Protected Storage as a "self-managing, self-healing NAS product that scales simultaneously in the dimensions of capacity and performance and offers built-in data protection." In short, it combines a NAS filer with nearline storage for backup and recovery, HSM for policy-based file migration, self-management, content-addressable storage and disaster recovery tools. But lest you think it does everything--the equivalent of a storage Swiss Army knife--it does nothing for SAN block-level storage and is unlikely to beat high-end products from NAS industry leaders in terms of high speed, Taneja says.
Originally, NAS products were primarily appliances that combined hardware, the filer operating system and storage arrays in a single box. These devices can still be found at the low-end and the midrange markets. But increasingly, vendors allow the NAS operating system to be separated from the storage arrays to create a NAS head. NAS heads can be used as gateways to a consolidated SAN that provides both file- and block-level storage.
It seems like a good idea, but "today's NAS customers don't want all that. They want NAS because it is simple, easy and cheap," GlassHouse's Foskett says. Should storage become a centralized utility, the NAS head would offer a way to leverage block storage for files. But the storage utility isn't a reality today.
Still, NAS heads may yet gain traction. "It gives you a nice front end to both files and blocks on the back end. And as iSCSI takes hold, there will be less of a need to differentiate file and block storage," says Scott Robinson, CTO, DataLink Corp., a storage integrator based in Chanhassen, MN. When that day comes, the NAS head would open up interesting opportunities in terms of the use of primary and secondary storage tiers and information life cycle management (ILM).
Today most companies are not taking advantage of all the capabilities vendors are packing into their NAS products, although the best products in the market can almost match SAN technology in features and capability. To them, NAS remains easy and cheap file storage--period. And despite being widely deployed in the enterprise, NAS remains a stealth technology while SANs attract the most attention.
This was first published in March 2004