21020690 B 6500 Disk Array User’s Guide
Chapter 1 Description
Page 1 - 4 Features and Options
Features and Options
SCSI
Compatibility
• Conforms to SCSI-2 standards.
• 8- or 16-bit data transfers on host interface.
• Single-ended or differential SCSI interface.
• Compatible with industry-standard SCSI adapters and driv ers, inc luding
all Ciprico SCSI host bus adapters.
Controller
Board
SCSI-2 to ATA RAID-3 disk array controller with a 16-bit host SCSI in terface
and 9 ATA interfaces.
Disk Drives 9 ATA disk drives (8 data, one parity).
Redundancy Continued operation after failure of a single data drive.
Parallel Disk
Array
Architecture
Ciprico’s 6500 parallel disk array communicates with an initiator (or hos t) via
the SCSI-2 industry standard interface. The array’s design combines current
drive technology with an advanced controller board, where data is “striped”
across eight drives at once. Byte-striping involves partitioning of data into
bytes, with each byte assigned to a particular drive and all bytes written to the
drives simultaneously. Using this method, transfer rates for read/write
functions are significantly faster than a single disk drive having the same
capacity.
Parity Drive Improved reliability and data availability are provided by a dedicated parity
drive. As data is striped to the eight data drives, parity data is generated and
stored on the parity drive. Parity information is used to verify data integrity
when reading from the drives, and to regenerate data if a drive should fail and
is replaced. A single drive failure will not degrade overall performance. Use of