Bake-Off: Network-Attached Storage

CRN Test Center reviewers set out to examine middle-of-the-road NAS products that support 2 Tbytes to 4 Tbytes of storage space and have a Gigabit Ethernet interface. The five products that made the cut were Adaptec Inc.'s Snap Server 520, Buffalo Technology Inc.'s TeraStation Pro II, Hewlett-Packard Co.'s ProLiant DL320s Storage Server, LaCie's Ethernet Disk, and Netgear Inc.'s ReadyNAS NV+. These capacities represent the maximum for each unit, which were not the same as the as-tested capacity.

Methodology
Reviewers calculated technical rankings by looking at performance, feature set and capacity-per-dollar. Capacity-per-dollar was calculated on a standard 2-Tbyte storage system. Channel programs were also considered.

In the interest of standardizing storage types, each system was configured with a single RAID 5 array setup at the largest size possible. Each unit was connected to the same switch as the testing PC.

Two tests measured performance. First, two directories with various file types were copied from the testing PC to the NAS and back again. The 1.2-Gbyte directory contained 23 files and the 3.2-Gbyte directory had 41. Operations were timed. Then Iozone testing software measured I/O performance on files from 32 Mbytes to 10 Gbytes. Results were plotted to see which system had the best overall performance across various file sizes.

Other considerations included environmental factors such as noise level, power draw and heat output; feature set; applications; types of connectivity; supported platforms; failover capabilities and management options.

Running the Numbers
Iozone tests both file sizes and record sizes when measuring read/write speeds. When the results were plotted, HP ProLiant DL320s Storage Server creamed the competition. It measured 815,151 KBps (796 MBps) on writing a 32-Mbyte file with 64-Kbyte records, while the next highest performer, LaCie Ethernet Disk, measured 285,787 KBps (279 MBps). Oddly enough, LaCie Ethernet Disk has less features but consistently outperformed Adaptec Snap Server 520 across all file sizes, while Buffalo's TeraStation Pro II and Netgear's ReadyNAS NV+ had virtually identical results. Buffalo and Netgear win points for consistency—their speed remained essentially the same regardless of file size. After 128 Mbytes, however, LaCie's read/write speeds dropped close to Adaptec's speeds, which remained slightly better than Buffalo and Netgear. The HP results remained consistently high, but had a sharp decline after 1 Gbyte, bringing it closer to the rest of the competition in order of magnitude.

Next: HP ProLiant DL320s Storage Server