Dell MD3600F Computer Hardware User Manual


 
50 Planning: MD3600f Series Storage Array Terms and Concepts
If a redundant RAID controller module fails with an existing disk group process,
the process on the failed controller is transferred to the peer controller. A
transferred process is placed in a suspended state if there is an active disk group
process on the peer controller. The suspended processes are resumed when the
active process on the peer controller completes or is stopped.
NOTE: If you try to start a disk group process on a controller that does not have an
existing active process, the start attempt fails if the first virtual disk in the disk group
is owned by the other controller and there is an active process on the other
controller.
RAID Background Operations Priority
The storage array supports a common configurable priority for the following
RAID operations:
Background initialization
•Rebuild
•Copy back
Virtual disk capacity expansion
Raid level migration
Segment size migration
Disk group expansion
Disk group defragmentation
The priority of each of these operations can be changed to address
performance requirements of the environment in which the operations are to
be executed.
NOTE: Setting a high priority level impacts storage array performance. It is not
advisable to set priority levels at the maximum level. Priority should also be
assessed in terms of impact to host server access and time to complete an
operation. For example, the longer a rebuild of a degraded virtual disk takes, the
greater the risk for potential secondary disk failure.
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