AMCC 3ware 9000 Series, User Manual

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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).
„
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 degraded 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).
„
Import a unit
. Attach a set of disk drives with an existing configuration to
a controller and make the controller aware of the unit. Does not affect the
data on the drives.
„
Initialize. Put the redundant data on the drives of redundant units into a
known state so that data can be recovered in the event of a disk drive
failure. For RAID 1 and 10, initialization copies the data from the lower
port to the higher port. For RAID 5 and 50, initialization calculates the
RAID 5 parity and writes it to disk (background initialization) or writes
zeroes to all of the drives in the array (foreground initialization).
Initialization does not erase user data if done while the operating system
is running. However, RAID 5 initialization done through the 3ware BIOS
does erase any existing data.
„
JBOD.
An unconfigured single drive. The acronym is derived from “just a
bunch of disks.” Note that earlier versions of the 3ware RAID controller
exported JBODs to the OS. By default, this is not the case in 9000-series
controllers. However, a policy in 3BM can be set that allows JBODs to be
seen by the OS. By default, individual drives must be configured as
Single Disks in order to be made available to the OS.
„
Mirrored disk array.
A pair of drives on which the same data is written,
so that each provides a backup for the other. If one drive fails, the data is