Dot Hill Systems RAIDCore, User Manual

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RAIDCore User Manual 17
Background array initialization
(BGI) The background initialization of a redundant array creates the parity
data that allows the array to maintain its redundant data and survive a
disk failure.
Because background initialization helps RAIDCore identify and
correct problems that might occur with the redundant data at a later
time, background initialization is similar to check consistency.
Background initialization allows a redundant array to be used
immediately. Data is not lost if a disk goes offline prior to completion
of the BGI process.
Cache support for arrays Various array-caching options are supported: No Cache, Read
Cache, Write Back Cache, Read + Write Back Cache.
Cache support for disks Various disk-caching options are supported: No Cache, Disk Read
Ahead, Disk Write Back, Disk Read Ahead + Write Back.
Consistency Check A Consistency Check is a background operation that verifies and
corrects the mirror or parity data for fault-tolerant disks. It is
recommended that a Consistency Check be run periodically on the
disks.
By default, a Consistency Check automatically corrects mirror or
parity inconsistencies.
A Consistency Check can be scheduled or started manually by the
system user.
Controller spanning A unique feature of RAIDCore that allows very wide arrays to be
created from disks connected to different controllers.
NOTE:
This feature is available only with RAIDCore
VST.
See Supported Controllers on page 15.
Disk roaming With disk roaming, SAS/SATA cables can be disconnected from
their disks and shuffled without confusing RAIDCore.
NOTE:
Disconnect the SAS/SATA cables from the disks
only when the system is offline.
Disk roaming also allows:
• Disks to be moved to different slots in the backplane.
RAIDCore detects which disks belong to which arrays,
regardless of where the disks are moved in the backplane.
• Disk(s) to be moved between systems.
Table 3 Features of RAIDCore (continued)
RAIDCore Feature Description