HP P6000 Continuous Access Implementation Guide (T3680-96431, August 2012)

back to the state they were in as of no longer than 6 hours ago. To achieve this objective, you
need to be making backups or other data copies at least every 6 hours.
RTO Recovery Time Objective. The time needed to recover from a disaster—usually determined by
how long you can afford to be without your systems.
RWP Replication Workload Profiler
S
SAN Storage area network. A network of storage devices and the initiators that store and retrieve
information on those devices, including the communication infrastructure.
server-based
management
Management from a server. See also management server.
SFP Small Form Factor Pluggable transceiver.
snapclone A copy that begins as a fully allocated snapshot and becomes an independent virtual disk. Applies
only to the HP EVA.
snapshot A nearly instantaneous copy of the contents of a virtual disk created without interrupting operations
on the source virtual disk. Snapshots are typically used for short-term tasks, such as backups.
source The virtual disk, DR group, or virtual array where I/O is stored before replication. See also
destination.
SPOF Single point of failure.
standby
management
server
A backup management server. See management server.
storage system A system consisting of one or more arrays; synonymous with virtual array. See also array.
synchronous A term used to describe computing models that perform tasks in chronological order without
interruption. In synchronous replication, the source waits for data to be copied at the destination
before acknowledging that it has been written at the source. See also asynchronous.
V
virtual array Synonymous with disk array and storage system; a group of disks in one or more disk enclosures
combined with control software that presents disk storage capacity as one or more virtual disks.
See also virtual disk.
Virtual Controller
Software (VCS)
See controller software.
virtual disk Variable disk capacity that is defined and managed by the array controller and presented to
hosts as a disk. May be called Vdisk in the user interface.
Vraid The level to which user data is protected. Redundancy is directly proportional to cost in terms of
storage usage; the greater the level of data protection, the more storage space is required. See
also: Vraid0, Vraid1, Vraid5, Vraid6.
Vraid0 Optimized for I/O speed and efficient use of physical disk space, but provides no data
redundancy.
Vraid1 Optimized for data redundancy and I/O speed, but uses the most physical disk space.
Vraid5 Provides a balance of data redundancy, I/O speed, and efficient use of physical disk space.
Vraid6 Offers the features of Vraid5 while providing more protection for an additional drive failure, but
uses additional physical disk space.
W
WDM Wavelength Division Multiplexing. The ability to have multiple optical signals share a single
optical cable.
write history log A dedicated area of disk capacity used to record host write I/O to the source virtual disks.
134 Glossary