Intel 12Gb/s, Руководство пользователя

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34 12Gb/s Intel® RAID Controllers User Guide
hot spare An idle, powered on, standby drive that is ready for immediate use in case of drive
failure. A hot spare does not contain any user data. A hot spare can be dedicated to a
single redundant array or it can be part of the global hot-spare pool for all arrays
managed by the controller.
When a drive fails, the controller firmware automatically replaces and rebuilds the data
from the failed drive to the hot spare. Data can be rebuilt only from virtual drives with
redundancy (RAID levels 1, 5, 6, 10, 50, and 60; not RAID level 0), and the hot spare
must have sufficient capacity.
I
internal SAS device A SAS device installed inside the computer cabinet. These devices are connected by
using a shielded cable.
M
main memory The part of computer memory that is directly accessible by the CPU (usually
synonymous with RAM).
N
NVRAM Acronym for nonvolatile random access memory. An EEPROM (electronically
erasable read-only memory) chip that stores configuration information. See EEPROM .
P
PCI Acronym for peripheral component interconnect. A high-performance, local bus
specification that allows the connection of devices directly to computer memory. The
PCI Local Bus allows transparent upgrades from 32-bit data path at 33 MHz to 64-bit
data path at 33 MHz, and from 32-bit data path at 66 MHz to 64-bit data path at 66
MHz.
PCI Express Acronym for peripheral component interconnect Express. A high-performance, local
bus specification that allows the connection of devices directly to computer memory.
PCI Express is a two-way, serial connection that transfers data on two pairs of point-
to-point data lines. PCI Express goes beyond the PCI specification in that it is intended
as a unifying I/O architecture for various systems: desktops, workstations, mobile,
server, communications, and embedded devices.
peripheral devices A piece of hardware (such as a video monitor, drive, printer, or CD-ROM) used with a
computer and under the control of the computer. SCSI peripherals are controlled
through an Intel
®
RAID 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.
R
RAID Acronym for Redundant Array of Independent Disks (originally Redundant Array of
Inexpensive Disks). An array (group) of multiple independent drives managed together
to yield higher reliability, performance, or both exceeding that of a single drive. The
RAID array appears to the controller as a single storage unit. I/O is expedited because
several drives can be accessed simultaneously. Redundant RAID levels (RAID levels
1, 5, 6, 10, 50, and 60) provide data protection.