HP SureStore E Disk Array 12H User's and Service Manual (C5445-90901, September 1999)

Glossary
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Glossary
In either RAID 0/1 or RAID 5 mode, the data is stored with Data
Redundancy, so that at any time, a single disk failure will cause no loss
of user data and no interruption of data transfer. While Logical Drive
space is defined and thus fixed, the available amount of free space can
vary, because Dynamic Data Migration is able to switch user data from
RAID 0/1 to RAID 5 mode as the Disk Modules become full. Similarly,
installation of additional Disk Modules allows more data to be stored in
RAID 0/1 mode, thus increasing the disk array performance.
Enclosure The box, or set of boxes containing one or more SCSI devices. It may
provide the power, cooling, mechanical support, and external electronic
interfaces for those devices.
EPROM Erasable Programmable Read-Only Memory.
FC Device A device that uses Fibre Channel technology.
Fast/Wide Fast/Wide SCSI is a 68-pin bus implementation that utilizes some of
the data lines of the bus for address lines.
Fibre Channel–Arbitrated Loop One of three existing Fibre Channel (FC) topologies, in which two to
126 devices are interconnected serially in a single loop circuit. The
arbitrated loop topology supports all classes of service and guarantees
in order of delivery of frames when the source and destination are on
the same loop.
Format The process of reinitializing the disk media. A format destroys all data
on the portion of the disk media being formatted. Two types of formats
are available: a hard format that overwrites all data on the disk media,
and a soft format that simply rewrites the headers.
HBA The HBA, or Host Bus Adapter, is an internal card that is located in the
host computer. Each HBA can connect to several SCSI devices.
Hot Pluggable Devices are Hot Pluggable if they can be removed while the host
computer system is running. When the disk array is configured with
redundant controllers and power supplies, all devices are Hot
Pluggable.