HPE XP7 User Manual page 356

CSV
Comma-separated value.
Control Unit (Command Unit, CU)
The storage space attached to a DKC can be organized by grouping similarly configured logical
devices (LDEVs) with unique CU images. The CUs are numbered sequentially. An XP or an XP7 disk
array supports a certain number of CUs depending on the disk array model. Each control unit can
manage multiple LDEVs. Therefore, to uniquely identify a particular LDEV, you need the CU and the
LDEV numbers.
D
DASD Fast Write (DFW)
The DFW is the function of a storage controller that allows caching of active write data without
exposure of data loss. This is achieved by journaling of the active write data in the NVS.
Disk Adapter (DKA)
The hardware component that controls the transfer of data between the drives and cache. A DKA
feature consists of a pair of boards. In an XP disk array, the DKA is one of the two PCB types that
contains the MPs.
Disk array
Disk array, or just array, is a complete storage system, including the control and logic devices, storage
devices (HDD, SSD), connecting cables, and racks
Disk Controller (DKC)
The hardware component that manages front-end and back-end storage operations. The term DKC is
sometimes used to refer to the entire RAID storage system.
Disk Processor (DKP)
In the XP disk arrays, the MP that resides on a DKA is addressed as the DKP.
DKPs does not exist in the P9500/XP7 disk arrays. All the MPs/DKPs form part of the MP blades in
the P9500/XP7 disk arrays.
DKU
Disk cabinet unit. The array cabinet that houses the physical disks.
Device Special File (DSF)
In the non windows systems, the DSF is an interface for a device driver that appears in a file system
as if it were an ordinary file. In the Windows systems, the DSF allows the software to interact with a
device driver using the standard input or the output system calls.
E
emulation mode
The LDEVs associated with each RAID group are assigned an emulation mode that makes them
operate like OPEN system disk drives. The emulation mode determines the size of an LDEV.
OPEN-3: 2.46 GB
OPEN-8: 7.38 GB
OPEN-9: 7.42 GB
OPEN-E: 13.56 GB
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