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Hardware terminology

Learn how the hardware terms apply to your storage array.

ComponentDescription
Storage arrayA storage array includes the shelves, controllers, drives, software, and firmware.
ShelfA shelf is an enclosure installed in a cabinet or rack. It contains the hardware components for the storage array. There are two types of shelves: a controller shelf and a drive shelf. A controller shelf includes controllers and drives. A drive shelf includes input/output modules (IOMs) and drives.
ControllerA controller consists of a board, firmware, and software. It controls the drives and implements the System Manager functions.
DriveA drive is an electromagnetic mechanical device or solid state memory device that provides the physical storage media for data.
BayA bay is a slot in the shelf where a drive or other component is installed.
Drive shelfA drive shelf, also called an expansion shelf, contains a set of drives and two input/output modules (IOMs). The IOMs contain SAS ports that connect a drive shelf to a controller shelf or to other drive shelves.
Controller shelfA controller shelf contains a set of drives and one or more controller canisters. A controller canister holds the controllers, host interface cards (HICs), and batteries.
Power/fan canisterA power/fan canister is an assembly that slides into a shelf. It includes a power supply and an integrated fan.
IOM (ESM)An IOM is an input/output module that includes SAS ports for connecting the drive shelf to the controller shelf.
Note
In previous controller models, the IOM was referred to as an environmental service module (ESM).
SFPAn SFP is a Small Form-factor Pluggable (SFP) transceiver.