HP 3PAR T-Class Installation and Deinstallation Guide

active VLUN The connection of a virtual volume and a LUN for a particular host on a particular port. An active
VLUN is created when a VLUN template is applied to the current system state. See also VLUN
template.
admin space See snapshot administration space.
admin volume The base volume that is used by the system to store administration data such as the system event
log. The admin volume is created as part of the storage system installation and setup process.
administration
space
See snapshot administration space.
AL_PA See arbitrated loop physical address.
alert An event that requires intervention by the user.
arbitrated loop
physical address
(AL_PA)
A unique 8-bit value used to identify Fibre Channel devices on an arbitrated loop.
backup node See virtual volume backup node.
base volume The original virtual volume from which a series of snapshots can be created.
battery backup
unit (BBU)
A unit containing two strings of batteries. Each battery backup unit supplies two controller nodes
with enough current to write the cache to IDE drives in the event of a power interruption.
battery tray An enclosure that inserts into a EIA-standard rack to house a maximum of four battery backup
units.
BBU See battery backup unit.
cabinet An enclosure that houses the components of a storage system. A cabinet is made up of a frame
on four wheels, cosmetic panels, a rear door, an EIA-standard rack, PDUs, power cords, and
bezels.
cache memory
page (CMP)
A 16-KB block of control cache memory whereI/O requests are stored.
cage See drive cage.
chassis bay A space in a rack into which a battery tray, drive chassis, controller node, or service processor
is inserted.
child volume A virtual volume (virtual or physical copy) made from a parent volume.
chunklet A 256-MB block of contiguous space on a physical disk.
chunklet logging An action by the system that occurs when a chunklet is unavailable (for example, the disk is not
ready). The chunklet is placed in logging mode, where data that is supposed to be written to the
chunklet is instead written to a log. If the chunklet becomes available again, the system places
the chunklet in playback mode, where the data is read from the log and written to the appropriate
chunklet.
clean chunklet A chunklet to which no data has been written.
cluster A group of controller nodes connected to the same storage system midplane. The nodes in a
cluster operate as a unified system, separate from any other clusters that can share the same
service processor.
CMP See cache memory page.
common
provisioning group
(CPG)
A set of logical disks from which virtual volumes and virtual copies can be created that are
capable of allocating storage on demand.
control cache Memory modules that support the microprocessors located in a controller node.
control cache
DIMM
A single control cache memory module.
controller node An individual device that works together with other controller nodes to cache and manage data
in a storage system and to provide hosts with a coherent, virtualized view of the storage.
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