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SAN (S
TORAGE
A
REA
N
ETWORK
)—A high-performance, typically enterprise-level
network that attaches disk storage subsystems to servers. The storage devices are
accessible to multiple hosts at the same time.
SAS (S
ERIAL
A
TTACHED
SCSI) — SAS is a serial, point-to-point, enterprise-level
device interface that leverages the proven Small Computer System Interface (SCSI)
protocol set. The SAS interface provides improved performance, simplified cabling,
smaller connectors, lower pin count, and lower power requirements when compared to
parallel SCSI. SAS physical disks are supported only by the PERC S300 controller.
SATA (S
ERIAL
A
DVANCED
T
ECHNOLOGY
A
TTACHMENT
)—A physical storage
interface standard, is a serial link that provides point-to-point connections between
devices. The thinner serial cables allow for better airflow within the system and permit
smaller chassis designs. The PERC S100 controller and PERC S300 controller leverage
a common electrical and physical connection interface that is compatible with Serial
ATA technology.
SCSI (S
MALL
C
OMPUTER
S
YSTEM
I
NTERFACE
)—A standard that allows multiple
devices to be connected in a daisy-chain format. The fastest hard-drives are SCSI-
based, rather than IDE-based.
S
PANNING
— The method by which nested RAID levels (such as RAID 10) are
constructed from multiple sets of basic, or single RAID types. For example, a RAID 10
is made up of multiple sets of RAID 1 arrays where each RAID 1 set is considered a
span. Data is then striped (RAID 0) across the RAID 1 spans to create a RAID 10
virtual disk. Spanning is generally used when referencing these nested RAID levels.
S
PARE
— A physical disk available to replace another physical disk in case that
physical disk fails.
SSD (S
OLID
S
TATE
D
ISK
)—A high-performance storage media that contains no
moving parts. It contains a memory board, a memory board bus, a CPU, and a battery
card.
S
TORPORT
— The Storport driver has been designed to replace SCSIport and work
with Windows 2003 and beyond. In addition, it offers better performance for newer
RAID controller protocols (like SAS), provides higher I/O throughput rates, improves
manageability, and has an upgraded miniport interface. For example, while SCSIport
allows a maximum of 254 commands per controller, Storport allows 254 commands
per logical unit number (LUN).
S
TORAGE
A
RRAYS
— A storage entity that is managed entirely by storage
management software. A storage array consists of a collection of physical components
(drives, controllers, fans, and power supplies) and logical components (such as virtual
disks). A storage array can span multiple physical enclosures.
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