IBM ServeRAID M5025, Руководство пользователя

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B-3
peripherals are controlled through a ServeRAID SAS/SATA controller
(host adapter).
PHY The interface required to transmit and receive data packets transferred
across the serial bus.
Each PHY can form one side of the physical link in a connection with a
PHY on a different SATA device. The physical link contains four wires
that form two differential signal pairs. One differential pair transmits
signals, while the other differential pair receives signals. Both differential
pairs operate simultaneously and allow concurrent data transmission in
both the receive and the transmit directions.
RAID Acronym for Redundant Array of Independent Disks (originally
Redundant Array of Inexpensive Disks). An array of multiple independent
physical disks managed together to yield higher reliability and/or
performance exceeding that of a single physical disk. The RAID array
appears to the controller as a single storage unit. I/O is expedited
because several disks can be accessed simultaneously. Redundant
RAID levels (RAID levels 1, 5, 6, 10, 50, and 60) provide data protection.
RAID level A set of techniques applied to disk groups to deliver higher data
availability, and/or performance characteristics to host environments.
Each virtual disk must have a RAID level assigned to it.
SAS Acronym for Serial Attached SCSI. A serial, point-to-point,
enterprise-level device interface that leverages the proven SCSI protocol
set. The SAS interface provides improved performance, simplified
cabling, smaller connections, lower pin count, and lower power
requirements when compared to parallel SCSI. The SAS controller
leverages a common electrical and physical connection interface that is
compatible with Serial ATA.
The ServeRAID SAS/SATA controller supports the SAS protocol as
described in the
Serial Attached SCSI Standard , version 1.1 . The
controller also supports the Serial ATA II (SATA II) protocol defined by
the
Serial ATA Specification, Version 1.0a , and the Serial ATAII;
Extension to the Serial ATA Specification, Version 1.1 . SATA II is an
extension to SATA 1.0a.
The ServeRAID M5025 SAS/SATA controller is a versatile controller that
provides the backbone of both server and high-end workstation