Adaptec MAN-00005-UG, Инструкция по установке и эксплуатации

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A magnetically coated disk substrate that spins inside a
disk drive and is used as the storage medium for digital
data.
Hard Disk Drive (HDD)
The main data storage unit of a computer.
Host
Any computer system to which disks are attached and
accessible for data storage and I/O.
Host I/O Bus
An I/O bus used to connect a host computer to storage
systems or storage devices.
Hot Plug
The process of adding or removing a device from a bus
while transactions involving other devices are occurring
over the bus. See also PCI Hot Plug.
Hot Replacement of Disks
The design of all controllers allows for the replacement of
failed hard disk drives without interruption of system
service. In the event of a SCSI drive failure on a properly
configured system (where the data redundancy features of
the controller are used), the system generates a message to
alert the system operator. When a replacement drive
becomes available, the system operator can remove the
failed disk drive, install a new disk drive, and instruct the
controller to “rebuild” the data on the new drive, all
without interrupting system operations. Once the rebuild is
complete, the controller will be brought back into a fault
tolerant state. See also Hot Swap.
Hot Spare
A physical disk drive not part of a system drive that the
controller can use to automatically rebuild a critical system
drive. The hot spare drive must have at least as much
capacity as the largest disk drive in the array or the rebuild
may not start.
Hot Standby
A redundant component in a fault tolerant storage system
that has power applied and is ready to operate, but which
does not perform its task as long as the primary component
for which it is standing by is functioning properly. See also
Hot Replacement of Disks and Hot Spare.
Hot Swap
The exchange of a replacement unit in a storage system for
a defective unit. The exchange requires human
intervention, but the system can continue to perform its
normal functions (compare with Auto Swap, Cold Swap,
and Warm Swap).
I
Internal RAID Controller
A controller circuit board that resides inside a computer or
server. An internal RAID controller resides on a bus, such
as the PCI bus. Examples of internal RAID controllers
include the AcceleRAID
™
and eXtremeRAID
®
families.
I/O
Input/Output, the transmission of information between an
external source and the computer.
I/O Bottleneck
Any resource in the I/O path whose performance limits the
performance of a storage or I/O system.
I/O Bus
Any path used for the transfer of data and control
information between I/O adapters and storage controllers
or storage devices. See also Bus.
I/O Intensive
An application whose performance depends strongly on the
performance of the I/O system.
I/O Per Second
Number of I/O transactions per second.
J
Java
A programming language expressly designed for use in the
distributed environment of the Internet and enforces a
completely object-oriented view of programming. Java can
be used to create complete applications that may run on a
single computer or be distributed among servers and clients
in a network. It can also be used to build small application
modules or applets for use as part of a Web page.