HP P6000 Replication Solutions Manager User Guide (T3680-96089, October 2012)

Glossary
A
ABM array-based management
array Synonymous with storage array, storage system, and virtual array. A group of disks in one or
more disk enclosures connected to two controllers running controller software that presents disk
storage capacity as one or more virtual disks. See also virtual array, storage system.
array-based
management
A management structure in which HP P6000 Command View is installed on the management
module within the array controller enclosure.
asynchronous A term used to describe computing models that eliminate timing dependencies between sequential
processes. In asynchronous replication, the array controller acknowledges that data has been
written at the source before the data is copied at the destination. Asynchronous write mode is an
optional DR group property. See also synchronous.
B
bandwidth The transmission capacity of a link or system, usually measured in bits per second (b/s).
bandwidth latency
product
The measurement of the ability to buffer data; the raw transfer speed in bytes/second times the
round-trip latency in seconds.
bidirectional An array that contains both source and destination virtual disks. A bidirectional configuration
allows multidirectional I/O flow among several arrays.
C
container Virtual disk space that is preallocated for later use as a snapclone, snapshot, or mirrorclone.
controller software Software used by array controllers to manage all aspects of array operations.
copy set A source-destination pair of virtual disks that are members of a DR group.
D
data currency A measure of how current the last I/O on the DR group destination member is when compared
to the last I/O written to the DR group source member. The time difference between the last I/O
written to the source member and the last I/O written to the destination member represents the
amount of data that would be lost if the source member was no longer available, (assuming a
non-recoverable event at the source site). See also RPO.
DC-Management Dynamic Capacity Management. A feature enabling you to extend or shrink the size of a host
volume.
default disk group The disk group created when the array is initialized. The disk group must contain a minimum of
eight disks. The maximum is the number of installed disks.
destination The targeted recipient (for example, array or virtual disk) of replicated data.
disk group A named group of disks selected from all the available disks in a disk array. One or more virtual
disks can be created from a disk group. Also refers to the physical disk locations associated with
a parity group.
DR group Data Replication group. A logical group of virtual disks in a remote replication relationship with
a corresponding group on another array.
DR relationship When one array mirrors data to a second, remote array, they are said to have a DR relationship.
E
enabled host A host that is equipped with a replication manager host agent.
enhanced
asynchronous
A write mode in which all host write I/Os are added to the write history log (WHL). The controller
then acknowledges that data has been written at the source before the data is copied at the
destination.
290 Glossary