HP SureStore E SAN Manager LUN Management Administrator's Guide

Glossary 213
Glossary
Logical Unit Number (LUN)
A numeric value assigned to a logical unit. Most disk drives are considered logical unit
number zero. RAID devices can often be divided into multiple LUNs, which may have
LUN numbers other than zero. LUNs can be thought of as separate storage devices for
operational purposes, although physically that may not be the case.
Mirror Set
A set of partitions used for disk mirroring.
Partition
A portion of a physical disk that is treated as a logical drive.
Partition Map
Information that maps the layout of partitions on a device.
Physical Disk
A physical device that is associated with a logical unit number. A physical disk
represents a raw storage component before building logical partitions out of it.
Scalability
The ability to increase the number of LUNs and hosts on the SAN.
Share Group
A group of hosts that share designated storage; for example, clustered servers could
share SAN Manager LM devices within a share group.
Single System Image
Ability of a collection of individual resources, such as hosts or storage, to appear to
users as a unified computing resource.
Storage Area Network (SAN)
A topology-independent network designed to move data between storage devices and
computer systems at high speed.