HP D5970A - NetServer - LCII Installation And Configuration Manual page 138

Glossary
logical drive in the array. You cannot use online capacity expansion on logical
drives that span arrays (RAID levels 10, 30, or 50).
Channel: An electrical path for the transfer of data and control information
between a disk and a disk adapter.
Format: The process of writing zeros to all data fields in a physical drive (hard
drive) and to map out unreadable or bad sectors. Because most hard drives are
factory formatted, formatting is usually only done if a hard disk generates several
media errors.
GB: A gigabyte; an abbreviation for 1,073,741,824 (2 to the 30th power) bytes
used for memory or disk capacities.
Hot Spare: An idle, powered-on, stand-by disk module ready for use should
another disk module fail. It does not contain any user data. Up to eight disk
modules can be assigned as hot spares for an adapter. A hot spare can be
dedicated to a single redundant array, or it can be part of the global hot-spare
pool for all the arrays controlled by the adapter. Only one hot spare can be
dedicated to a given array.
When a disk fails, the adapter's firmware automatically replaces and rebuilds the
data from the failed disk onto the hot-spare disk. Data can only be rebuilt from
logical drives with redundancy (RAID levels 1, 3, 5, 10, 30, or 50; not RAID 0),
and the hot-spare disk must have sufficient capacity. The system administrator
can replace the failed disk module and designate the replacement disk module as
a new hot spare.
Hot Swap Disk Module: Hot swap modules allow a system administrator to
replace a failed disk drive in a server without powering down the server and
suspending network services. The hot swap module simply pulls out from its slot
in the drive cage because all power and cable connections are integrated into the
server backplane. Then the replacement hot-swap module can slide into the slot.
Hot swapping only works for RAID 1, 3, 5, 10, 30, and 50 configurations.
I O: Intelligent Input/Output (I
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architecture independent of the network operating system and the peripheral
devices supported. I
modules (OSMs) and hardware device modules (HDMs). I
system performance by shifting I/O computations from the system CPUs to
dedicated I/O processors. It also makes driver management easier and less
expensive.
Initialization: The process of writing zeros to the data fields of a logical drive
and generating corresponding parity to put the logical drive in a Ready state.
Initializing erases previous data, generating parity so that the logical drive will
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O) is an industry-standard, I/O subsystem
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O uses drivers that are split into operating system services
2
O increases overall
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