Hitachi VSP G400 User Guide

journal group (JNLG)
In a Universal Replicator system, journal groups manage data consistency
between multiple primary volumes and secondary volumes. See also
consistency group (CTG).
journal volume
A volume that records and stores a log of all events that take place in
another volume. In the event of a system crash, the journal volume logs
are used to restore lost data and maintain data integrity.
In Universal Replicator, differential data is held in journal volumes until
you copy it to the S-VOL.
L
L1 pair
See layer-1 (L1) pair.
L2 pair
See layer-2 (L2) pair.
layer-1 (L1) pair
In a ShadowImage cascade configuration, a layer-1 pair consists of a
primary volume and secondary volume in the first cascade layer. You can
pair an L1 primary volume with up to three L1 secondary volumes. See
also cascade configuration.
layer-2 (L2) pair
In a ShadowImage cascade configuration, a layer-2 (L2) pair consists of a
primary volume and secondary volume in the second cascade layer. You
can pair an L2 primary volume with up to two L2 secondary volumes. See
also cascade configuration.
LBA
logical block address
LDEV
See logical device.
LDKC
See logical disk controller (LDKC).
306 Glossary
Hitachi Thin Image User Guide for Hitachi Virtual Storage Platform G Series and F Series

Hitachi VSP G400 Specifications

General

Brand	Hitachi
Model	VSP G400
Category	Storage
Language	English