8x00 family of Disk Arrays 4.01.00 installation and reference guide (AA-RW7SP-TE, September 2010)

Glossary

This glossary defines the terms used in this guide or related to this product. It is not a comprehensive

glossary of computer terms.

ALB Adaptive Load Balance (ALB) is a feature provided by the EVA DSM that utilizes

certain features supported by the array, to deliver better performance for host

I/O requests.

controller A hardware device that facilitates communication between a host and one or

more LUNs organized as an array.

DSM Device Specific Module

fabric A network that contains high-speed fiber connections resulting from the

interconnection of switches and devices. A fabric is an active and intelligent

non-shared interconnect scheme for nodes.

failover The automatic substitution of a functionally equivalent system component for a

component that has failed.

HBA Host Bus Adapter. An I/O device that serves as the interface connecting a host

system to the SCSI bus or SAN (Storage Area Network)

host The computer system on which the Multipath software is running.

LUN Logical Unit Number. The actual unit number assigned to a device by the RAID

system controller.

mode A user-selectable parameter that specifies path behavior during normal and

failure conditions. Paths can be set to one of the following modes:

• Preferred — Indicates the path you choose for the desired I/O paths. When

a path is in preferred mode, load balance is not enabled and the Load Bal-

ance Type displays as none.

• Alternate — Indicates a path that is used for device access and I/O activities

when the preferred path fails.

MPIO Multipathing Input/Output.

path A virtual communication route that enables data and commands to pass between

a host server and a storage device.

path state An attribute that describes the operational condition of a path. A path can exist

in one of the following states:

• Active — Path is currently used for the I/O stream or is available for load

balancing.

HP MPIO Full Featured DSM for EVA4x00/6x00/8x00 family of Disk Arrays 4.01.00 installation

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