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Automatic replace member with predicted failure
A
Replace Member
operation can occur when there is a SMART predictive failure reporting on a physical disk in a virtual disk. The
automatic
Replace Member
is initiated when the first SMART error occurs on a physical disk that is part of a virtual disk. The target disk
needs to be a hot spare that qualifies as a rebuild disk. The physical disk with the SMART error is marked as
failed
only after the successful
completion of the
Replace Member
. This prevents the array from reaching degraded state.
If an automatic
Replace Member
occurs using a source disk that was originally a hot spare (that was used in a rebuild), and a new disk
added for the
Replace Member
operation as the target disk, the hot spare reverts to the hot spare state after a successful
Replace
Member
operation.
NOTE:
To enable the automatic Replace Member, use the Dell OpenManage storage management application.
Patrol Read
The
Patrol Read
feature is designed as a preventative measure to ensure physical disk health and data integrity.
Patrol Read
scans and
resolves potential problems on configured physical disks. The Dell OpenManage storage management application can be used to start
Patrol Read
and change its behavior.
The following is an overview of
Patrol Read
behavior:
•
Patrol Read
runs on all disks on the controller that are configured as part of a virtual disk, including hot spares.
•
Patrol Read
does not run on physical disks that are not part of a virtual disk or are in
Ready
state.
•
Patrol Read
adjusts the amount of controller resources dedicated to
Patrol Read
operations based on outstanding disk I/O. For
example, if the system is busy processing I/O operation, then
Patrol Read
uses fewer resources to allow the I/O to take a higher
priority.
•
Patrol Read
does not run on any disks involved in any of the following operations:
– Rebuild
– Replace Member
– Full or Background Initialization
– CC
– RLM or OCE
NOTE:
By default, Patrol Read automatically runs every seven days on configured SAS and SATA hard drives. Patrol Read is
not necessary on SSD and is disabled by default.
For more information on
Patrol Read
, see the Dell OpenManage documentation at
Physical disk failure detection
Failed physical disks are detected and rebuilds automatically start to new disks that are inserted into the same slot. Automatic rebuilds can
also occur with hot spares. If you have configured hot spares, the controllers automatically try to use them to rebuild failed physical disks.
Using persistent hot spare slots
NOTE:
The persistent hot spare slot feature is disabled by default.
The PERC 10 series can be configured so that the system backplane or storage enclosure disk slots are dedicated as hot spare slots. This
feature can be enabled using the Dell OpenManage storage management application.
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Features