HP MPIO Full Featured DSM for P6x00 family of Disk Arrays 4.04.00 Installation and Reference Guide (757324-001, May 2014)

Glossary
This glossary defines terms used in this guide or related to this product and 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 Balance
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.
• Available — Path is currently available, but not used for device access.
The path is only in this state when no load balancing policy has been
selected for the LUN.
• Standby — Intermediate state of the path before it is initialized (made
ready for device access), normally will not be seen.
• Failed — Path is currently unusable for the I/O stream.
port A The relative number of an HBA. A specific port number is determined
according to its order of discovery by the Windows operating system. HBA's
include SCSI, Fibre Channel, and IDE adapter types.
SAN Storage Area Network. A configuration of networked devices for storage.
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