HP XP7 User Manual page 330

updated. The original snapshot of the volume is maintained by storing the to-be-changed data
blocks in the data pool.
DC data center
DCR Dynamic Cache Residency
DEV, dev device
device A physical or logical unit with a specific function.
device emulation Indicates the type of logical volume. Mainframe device emulation types provide logical volumes
of fixed size, called logical volume images (LVIs), which contain EBCDIC data in CKD format.
Typical mainframe device emulation types include 3390-9 and 3390-M. Open-systems device
emulation types provide logical volumes of variable size, called logical units (LUs), that contain
ASCII data in FBA format. The typical open-systems device emulation type is OPEN-V.
differential data Changed data in the primary volume not yet reflected in the secondary volume of a copy pair.
disk array Disk array, or just array, is another name for a RAID storage system.
disk controller The hardware component that manages front-end and back-end storage operations. The term
(DKC) DKC is also used to refer to the entire RAID storage system.
DKC disk controller. DKC can refer to the RAID storage system or the controller components.
DKCMAIN disk controller main. Refers to the microcode for the RAID storage system.
drive chassis The hardware component of the HP XP7 Storage that contains data drives and no controller
components. A drive chassis can also be called a disk unit (DKU).
dump A collection of data that is saved to a file when an error or crash occurs. The data is used by
support personnel to determine the cause of the error or crash.
Dump Tool Downloads Remote Web Console configuration information for backup and troubleshooting
purposes.
EBCDIC extended binary-coded decimal interchange code
ECKD extended count-key data
emulation The operation of the HP RAID storage system to emulate the characteristics of a different storage
system. For device emulation the mainframe host "sees" the logical devices on the RAID storage
system as 3390-x devices. For controller emulation the mainframe host "sees" the control units
(CUs) on the RAID storage system as 2107 controllers.
RAID storage system operates the same as the storage system being emulated.
emulation group A set of device emulation types that can be intermixed within a RAID group and treated as a
group.
env. environment
EXCTG See extended consistency group (EXCTG).
EXG external volume group
ext. external
extended A set of Continuous Access Journal Z journal groups in which data consistency is guaranteed.
consistency group When performing copy operations between multiple primary and secondary systems, the journal
(EXCTG) groups must be registered in an EXCTG.
external port A fibre-channel port that is configured to be connected to an external storage system for External
Storage operations.
external volume A logical volume whose data resides on drives that are physically located outside the HP RAID
storage system.
failback The process of switching operations from the secondary path or host back to the primary path
or host, after the primary path or host has recovered from failure. See also failover.
failover The process of switching operations from the primary path or host to a secondary path or host
when the primary path or host fails.
FBA fixed-block architecture
FC Fibre Channel; FlashCopy
330 Glossary