leaf volume
A layer-2 secondary volume in a ShadowImage cascade configuration.
The primary volume of a layer-2 pair is called a node volume. See also
cascade configuration
.
license key
A specific set of characters that unlocks an application and allows it to be
used.
local copy
See
in-system replication
.
logical device (LDEV)
An individual logical device (on multiple drives in a RAID configuration) in
the storage system. An LDEV might or might not contain any data and
might or miight not be defined to any hosts. Each LDEV has a unique
identifier, or address, within the storage system. The identifier is
composed of the logical disk controller (LDKC) number, control unit (CU)
number, and LDEV number. The LDEV IDs within a storage system do not
change.
An LDEV formatted for use by mainframe hosts is called a logical volume
image (LVI). An LDEV formatted for use by open-system hosts is called a
logical unit (LU).
logical disk controller (LDKC)
A group of 255 control unit (CU) images in the RAID storage system that
is controlled by a virtual (logical) storage system within the single
physical storage system. For example, the Hitachi Universal Storage
Platform V storage system supports two LDKCs, LDKC 00 and LDKC 01.
logical unit (LU)
A volume, or LDEV, created in an open storage system, or configured for
use by an open-systems host, for example, OPEN-V.
logical unit (LU) path
The path between an open-systems host and a logical unit.
logical unit number (LUN)
A unique management number that identifies a logical unit (LU) in a
storage system. A logical unit can be an end user, a file, a disk drive, a
port, a host group that is assigned to a port, an application, or virtual
partitions (or volumes) of a RAID set.
Glossary
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Hitachi Thin Image User Guide for Hitachi Virtual Storage Platform G Series and F Series