Setting Modification Priority; Assigning Global Hot Spares - Dell PowerVault MD3260 Cli Manual

Setting Modification Priority

Modification priority defines how much processing time is allocated for virtual disk modification operations. Time
allocated for virtual disk modification operations affects system performance. Increases in virtual disk modification
priority can reduce read/write performance. Operations affected by modification priority include:
• Copyback
• Reconstruction
• Initialization
• Changing segment size
• Defragmentation of a disk group
• Adding free capacity to a disk group
• Changing the RAID level of a disk group
The lowest priority rate favors system performance, but the modification operation takes longer. The highest priority rate
favors the modification operation, but the system performance might be degraded.
The set virtualDisk command enables you to define the modification priority for a virtual disk. The following
syntax is the general form of the command:
set (allVirtualDisks | virtualDisk
[virtualDiskName] | virtualDisks [virtualDiskName1
... virtualDiskNamen] | virtualDisk <wwid> |
accessVirtualDisk) modificationPriority=(highest |
high | medium | low | lowest)
The following example shows how to use this command to set the modification priority for virtual disks named
Engineering 1 and Engineering 2:
client>smcli 123.45.67.89 -c "set virtualDisks
[\"Engineering_1\" \"Engineering_2\"]
modificationPriority=lowest;"
The modification rate is set to lowest so that system performance is not significantly reduced by modification
operations.

Assigning Global Hot Spares

Hot spare physical disks can replace any failed physical disk in the storage array. The hot spare must be the same type
of physical disk as the physical disk that failed and must have capacity greater than or equal to any physical disk that
can fail. If a hot spare is smaller than a failed physical disk, the hot spare cannot be used to rebuild the data from the
failed physical disk. Hot spares are available only for RAID levels 1 or 5.
You can assign or unassign global hot spares by using the set physicalDisk command. To use this command, you
must perform these steps:
1. Identify the location of the physical disks by enclosure ID and slot ID.
2. Set the hotSpare parameter to TRUE to enable the hot spare or FALSE to disable an existing hot spare.
The following syntax is the general form of the command:
set (physicalDisk [enclosureID,slotID] |
physicalDisks [enclosureID0,slotID0 ...
enclosureIDn,slotIDn] hotSpare=(TRUE | FALSE)
42