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to another controller. Compare to Delete, which erases all unit configuration information from the drive.

•Exportable unit or drive. 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).

•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-(orInter-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. For 3ware SATA RAID controllers, initialize means to 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, initialization calculates the RAID 5 parity and writes it to disk (background initialization). This is sometimes referred to as resynching, and does not erase user data.

•Logical Units. This term is used in the 3ware CLI. It is usually shortened to “units.” These are block devices presented to the operating system. A logical unit can be a one-tier, two-tier, or three-tier arrangement. Spare, and Single logical units are examples of one-tier units. RAID 1 and RAID 5 are examples of two-tier units and as such will have sub-units. RAID 10 is an example of a three-tier unit and as such will have sub-sub-units.

•Migration. The process of changing the characteristics of a unit. The change can be to expand the capacity of the unit (OCE), change the stripe

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