Appendix A. Glossary
246
3ware Serial ATA RAID Controller User Guide
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Drive ID
. A unique identifier for a specific drive in a system. Also called a
port ID.
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Drive Number
. The SCSI number, or channel number, of a particular
drive.
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ECC.
Error correction code. ECC Errors are grown defects that have
occurred on a drive since it was last read.
•
ECC Error policy
. Determines whether an error detected during a rebuild
stops the rebuild or whether the rebuild can continue in spite of the error.
Specified by the Continue on Source Error During Rebuild unit policy.
•
EMS (Enclosure Management Services).
Chassis-monitoring functions
for environmental, power, mechanical monitoring, and control using the
I²C (chassis control) bus port.
•
Export a unit
. To remove the association of a unit with a controller. Does
not affect the data on the drives. Used for array roaming, when you want
to swap out a unit without powering down the system, and move the unit
to another controller. Compare to Delete, which erases all unit
configuration information from the drive.
•
Exportable unit or drive
. In 3BM (BIOS), exportable units and drives
are those that will be available to the operating system when you boot
your computer.
•
Fault tolerant
. A RAID unit which provides the ability to recover from a
failed drive, either because the data is duplicated (as when drives are
mirrored) or because of error checking (as in a RAID 5 unit).
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Firmware.
Computer programming instructions that are stored in a read-
only memory on the controller rather than being implemented through
software.
•
Grown defect.
Defects that arise on a disk from daily use.
•
Hot spare.
A drive that is available, online, and designated as a spare.
When a drive fails in a redundant unit, causing the unit to become
degraded, a hot spare can replace the failed drive automatically and the
unit will be rebuilt.
•
Hot swapping
. The process of removing a disk drive from the system
while the power is on. Hot swapping can be used to remove units with
data on them, when they are installed in hot-swap carriers. This is referred
to as array roaming. Hot swapping can also be used to remove and
replaced failed drives when a hot-swap carrier is used.
•
I²C-(or Inter-IC) bus
. A two-wire serial bus solution used as a control,
diagnostic, environmental, and power management for EMS (enclosure
management services).
