Hitachi Copy-on Write SnapShot, User Manual

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Glossary–3
Hitachi Simple Modular Storage Copy-on-Write SnapShot User’s Guide
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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
CLI
See command line interface.
cluster
A group of disk sectors. The operating system assigns a unique number
to each cluster and then keeps track of files according to which clusters
they use.
cluster capacity
The total amount of disk space in a cluster, excluding the space
required for system overhead and the operating system. Cluster
capacity is the amount of space available for all archive data, including
original file data, metadata, and redundant data.
command control interface (CCI)
Hitachi's Command Control Interface software provides command line
control of Hitachi array and software operations through the use of
commands issued from a system host. Hitachi’s CCI also provides a
scripting function for defining multiple operations.
command devices
Dedicated logical volumes that are used only by management software
such as CCI, to interface with the storage systems. Command devices
are not used by ordinary applications. Command devices can be shared
between several hosts.
command line interface (CLI)
A method of interacting with an operating system or software using a
command line interpreter. With Hitachi’s Storage Navigator Modular
Command Line Interface, CLI is used to interact with and manage
Hitachi storage and replication systems.
concurrency of S-VOL
Occurs when an S-VOL is synchronized by simultaneously updating an
S-VOL with P-VOL data AND data cached in the primary host memory.
Discrepancies in S-VOL data may occur if data is cached in the primary
host memory between two write operations. This data, which is not
available on the P-VOL, is not reflected on to the S-VOL. To ensure
concurrency of the S-VOL, cached data is written onto the P-VOL before
subsequent remote copy operations take place.
concurrent copy
A management solution that creates data dumps, or copies, while other
applications are updating that data. This allows end-user processing to
continue. Concurrent copy allows you to update the data in the files
being copied, however, the copy or dump of the data it secures does
not contain any of the intervening updates.