User Manual

Constellation.2 SAS Product Manual, Rev. K 12
3.0 General description
Constellation®.2 drives provide high performance, high capacity data storage for a variety of systems including engi-
neering workstations, network servers, mainframes, and supercomputers. The Serial Attached SCSI interface is
designed to meet next-generation computing demands for performance, scalability, flexibility and high-density stor-
age requirements.
Constellation®.2 drives are random access storage devices designed to support the Serial Attached SCSI Protocol as
described in the ANSI specifications, this document, and the SAS Interface Manual (part number 100293071) which
describes the general interface characteristics of this drive. Constellation®.2 drives are classified as intelligent periph-
erals and provide level 2 conformance (highest level) with the ANSI SCSI-1 standard. The SAS connectors, cables and
electrical interface are compatible with Serial ATA (SATA), giving future users the choice of populating their systems
with either SAS or SATA hard disk drives. This allows you to continue to leverage your existing investment in SCSI while
gaining a 6Gb/s serial data transfer rate.
The Self-Encrypting Drive models indicated on the cover of this product manual have provisions for “Security of Data
at Rest” based on the standards defined by the Trusted Computing Group (see www.trustedcomputinggroup.org).
The head and disk assembly (HDA) is sealed at the factory. Air recirculates within the HDA through a non-replaceable
filter to maintain a contamination-free HDA environment.
Note. Never disassemble the HDA and do not attempt to service items in the sealed enclosure (heads, media,
actuator, etc.) as this requires special facilities. The drive does not contain user-replaceable parts. Opening
the HDA for any reason voids your warranty.
Constellation®.2 drives use a dedicated load/unload zone at the outermost radius of the media to eliminate the possi-
bility of destroying or degrading data by landing in the data zone. The heads automatically go to the ramp load/
unload when power is removed from the drive.
An automatic shipping lock prevents potential damage to the heads and discs that results from movement during
shipping and handling. The shipping lock disengages and the head load process begins when power is applied to the
drive.
Constellation®.2 drives decode track 0 location data from the servo data embedded on each surface to eliminate
mechanical transducer adjustments and related reliability concerns.
The drives also use a high-performance actuator assembly with a low-inertia, balanced, patented, straight arm design
that provides excellent performance with minimal power dissipation.