The M2351 "Eagle" was a hard disk drive manufactured by Fujitsu with an SMD interface that was used on many servers in the mid-1980s. It offered an unformatted capacity of 470 MB^[1] in 10+1⁄2 inches (270 mm) (6U) of 19-inch rack space, at a retail price of about US$10,000.

The data density, access speed, reliability, use of a standard interface, and price point combined to make it a very popular product used by many system manufacturers, such as Sun Microsystems. The Eagle was also popular at installations of DEC VAX systems, as third-party storage systems were often dramatically more cost-effective and space-dense than those vendor-supplied.

The model 2351A incorporated eleven platters rotating at 3,960 rpm, taking half a minute to spin up. The Eagle used 10.5-inch-diameter (270 mm) platters, unlike most of its competitors, which still used the 14-inch (360 mm) standard set in 1962 by the IBM 1311. One moving head accessed each data surface (20 total), one more head was dedicated to the servo mechanism. The model 2351AF added 60 fixed heads (20 surfaces × 3 cylinders) for access to a separate area of 1.7 MB.

The Eagle achieved a data transfer rate of 1.8 MB/s (a contemporary 5+1⁄4-inch (130 mm) PC disk would only deliver 0.4 MB/s).

Power consumption (of the drive alone) was about 600 watts.

• "M2351 Magnetic Disk Unit". IPSJ Computer Museum. Information Processing Society of Japan. Retrieved 30 October 2021.
• neozeed (26 September 2009). "Fujitsu Super Eagle". Computer History Wiki. Tore Sinding Bekkedal (gunkies.org). Retrieved 30 October 2021.
• "Fujitsu M2351 Eagle - Functional Specifications". Peter's Sun3 Zoo. Archived from the original on 15 October 2016.