DELL 34XX User Manual

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running Linux. Typically, you need to change the host type only when you are setting up the storage 
array. The only time you might need to use this parameter is if you need to change how the storage array 
behaves relative to the hosts.
Before you can define the default host type, you need to determine what host types are connected to the 
storage array. To return information about host types connected to the storage array, you can use the 
show storageArray command with the defaultHostType parameter or hostTypeTable parameter. 
This command returns a list of the host types with which the RAID controller modules can communicate; 
it does not return a list of the hosts. The following examples show how to use the defaultHostType 
parameter and the hostTypeTable parameter:
client>smcli 123.45.67.89 -c "show storageArray defaultHostType;"
client>smcli 123.45.67.89 -c "show storageArray hostTypeTable;"
The following example shows how to define a specific default host type:
client>smcli 123.45.67.89 -c "set storageArray defaultHostType=11;"
The value 11 is the host type index value from the host type table.
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.
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