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Cyclic
redundancy check
CRC consists of a great number of bits computed as the data to be
protected and appended to the data.
D
Data disk
The disk for saving service data in RAID groups.
Defragment
The process of rewriting LUN data on disks, which helps to continue
the unoccupied free space among LUNs.
Degraded RAID
group
When a member disk in a RAID group fails, part or all of the redundancy
is lost.
Delete RAID
group
To delete a RAID group so that member disk in a RAID group becomes
a free disk.
Dirty page
The data that is stored in only the cache but not written into disks.
Disaster recovery
A system deployment solution aiming at reducing loss in disasters. A
set of disaster recovery system that is the same as the production system
is deployed as a backup to store the production data when a fault occurs
in the production system. The applications are switched over to the
disaster recovery system before the production system recovers. After
the production system recovers, the applications are switched back to
the production system.
Disk array
A set of disks from one or more commonly accessible disk subsystem,
combined with a body of control software. The control software presents
the disks' storage capacity to hosts as one or more virtual disks.
Disk location
Locate a hard disk, that is, determine the enclosure number and slot
number of the hard disk in the OceanStor storage system.
Disk enclosure
It consists of the following parts: expander board, hard disk, PEM/fan
module, and DIP switch board. System capacity can be expanded by
cascading multiple disk enclosures.
Disk utilization
The percentage of used capacity in the total available capacity.
Dynamic Storage
Tiering
A data moving and saving method, which permits system move files
between different tiers according to the access temperature.
Dynamic RAID
group expansion
A feature of adding member disks in a RAID group dynamically without
interrupting the normal services of the RAID group.
E
Expand the
member disk of
RAID group
dynamically
To add member disks in a RAID group without interrupting the normal
services of the RAID group.
Expander module
A component used for expanding.
OceanStor N8500 Clustered NAS Storage System
Installation Guide (for T Series V100R005)
C Glossary
Issue 02 (2015-09-22)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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