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For more information about virtual disk capacity expansion, see
Disk group expansion
Because the storage array supports hot-swappable physical disks, you can add two physical disks at a time for each disk group while the
storage array remains online. Data remains accessible on virtual disk groups, virtual disks, and physical disks throughout the operation. The
data and increased unused free space are dynamically redistributed across the disk group. RAID characteristics are also reapplied to the disk
group as a whole.
Disk group defragmentation
Defragmenting consolidates the free capacity in the disk group into one contiguous area. Defragmentation does not change the way in
which the data is stored on the virtual disks.
Disk group operations limit
The maximum number of active, concurrent disk group processes per installed RAID controller module is one. This limit is applied to the
following disk group processes:
•
Virtual disk RAID level migration
•
Segment size migration
•
Virtual disk capacity expansion
•
Disk group expansion
•
Disk group defragmentation
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.
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About your MD Series storage array