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NCQ (N
ATIVE
C
OMMAND
Q
UEUING
)—A command protocol for Serial ATA, that
allows multiple, outstanding commands to be active on a drive at the same time.
N
ON
-R
AID
C
ONFIGURATION
— Non-Raid data is data that already exists on a
replacement physical disk. The Non-Raid physical disk must be initialized before it
can be used with the PERC S100 controller or PERC S300 controller.
N
ON
-R
EDUNDANT
V
IRTUAL
D
ISK
— A non-redundant virtual disk is one which does
not have redundant data on physical disks that can be used to rebuild a failed physical
disk. A RAID 0 virtual disk consists of data striped across the physical disks, without
disk mirroring or parity to provide redundancy. This provides for high data throughput
but offers no protection in case of a physical disk failure.
N
S
— Acronym for nanosecond(s), one billionth of a second.
NTFS (N
EW
T
ECHNOLOGY
F
ILE
S
YSTEM
)—The file system used by Microsoft
Windows operating systems.
OCE (O
NLINE
C
APACITY
E
XPANSION
)—Operation to add capacity to an existing
virtual disk by adding an additional physical disk while the host system is active, and
without affecting data availability.
O
FFLINE
— A physical disk is offline when it is part of a virtual disk but its data is not
accessible to the virtual disk.
O
NLINE
— An online device is a device that is accessible.
P
ARITY
— An extra bit added to a byte or word to reveal errors in storage (in RAM or
disk) or transmission. Parity is used to generate a set of redundancy data from two or
more parent data sets. The redundancy data can be used to rebuild one of the parent
data sets. However, parity data does not fully duplicate the parent data sets. In RAID,
this method is applied to entire physical disks or stripe elements across all physical
disks in a virtual disk. Parity consists of dedicated parity, in which the parity of the data
on two or more physical disks is stored on an additional physical disk, and distributed
parity, in which the parity data are distributed among all the physical disks in the
system. If a single physical disk fails, it can be rebuilt from the parity of the applicable
data on the remaining physical disks.
P
ARTITION
— A logical structure on a contiguous segment of storage on a physical
disk or virtual disk that is recognizable by an operating system.
PCI
E
(P
ERIPHERAL
C
OMPONENT
I
NTERCONNECT
E
XPRESS
)—A high-speed
peripheral interconnect that can accommodate gigabit and chip-to-chip transfers.
PERC S100 V
IRTUAL
D
ISK
M
ANAGEMENT
, PERC S300 V
IRTUAL
D
ISK
M
ANAGEMENT
U
TILITY
— The PERC S100 Virtual Disk Management or PERC
S300 Virtual Disk Management utility (aka PERC Virtual Disk Management utility)
configures and maintains RAID virtual disks, and manages the RAID system. Because
the utility resides in the controller BIOS, its operation is independent of the operating
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