DELL 34XX Benutzerhandbuch

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stripe. A data stripe is the segment size that is multiplied by the number of physical disks in the disk group 
that are used for data transfers. In this case, multiple physical disks are used for the same request, but 
each physical disk is accessed only once.
For optimal performance in a multiuser database or file system storage environment, set your segment 
size to minimize the number of physical disks that are required to satisfy a data transfer request.
Security Type
The securityType parameter is valid for physical disks that are capable of selfencrypting disk (SED). 
With SED, the RAID controller module firmware can create a key and activate the physical disk security 
feature. The physical disk security feature encrypts data as the data is written to the physical disk and 
decrypts the data as the data is read from the physical disk. Without the key created by the RAID 
controller module, the data written to the physical disk is inaccessible.
Before you can set the securityType parameter to capable or enabled, you must create a storage array 
security key. Use the create storageArray securityKey command to create a storage array 
security key. The following commands are related to the security key:
• create storageArray securityKey
• set storageArray securityKey
• start secureErase (physicalDisk | physicalDisks)
• enable diskGroup [diskGroupName] security
Enclosure Loss Protection and Drawer Loss Protection
For enclosure loss protection to work, each physical disk in a disk group must be in a separate enclosure. 
If you set the enclosureLossProtect parameter to TRUE and have selected more than one physical 
disk from any one enclosure, the storage array returns an error. If you set the enclosureLossProtect 
parameter to FALSE, the storage array performs operations, but the disk group that you create might not 
have enclosure loss protection. Enclosure loss protection is not valid when you create virtual disks on 
existing disk groups.
The drawerLossProtect parameter defines if data on a virtual disk is accessible if a drawer fails. When 
you assign the physical disks, if you set the drawerLossProtect parameter to TRUE and select more 
than one physical disk from any one drawer, the storage array returns an error. If you set the 
drawerLossProtect parameter to FALSE, the storage array performs operations, but the disk group 
that you create might not have drawer loss protection. You must set the enclosureLossProtect 
parameter and the drawerLossProtect parameter to the same value. Either both the parameters must 
be TRUE or both must be FALSE. If the enclosureLossProtect parameter and the 
drawerLossProtect parameter are set to different values, the storage array returns an error.
Create Disk Pool
Description
This command creates a new disk pool based on the specified parameters. You can create the disk pool 
by entering either a list of physical disks or a type of physical disk that you want to use for the disk pool. 
Each disk pool must be created from a minimum of 11 physical disks specified. There is no upward limit of 
physical disks supported in a single disk pool, but the number cannot exceed the number of physical 
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