DELL MD3220 사용자 설명서

Configuration: Disk Groups and Virtual Disks

After you create virtual disks, you must map them to the host(s) connected to 

the array. 
Guidelines to configure host-to-virtual disk mapping:

• Each virtual disk in the storage array can be mapped to only one host or 

host group. 

• Host-to-virtual disk mappings are shared between controllers in the storage 

array. 

• A unique LUN must be used by a host group or host to access a virtual 

disk. 

RAID level 1 Ensure that each physical disk in a mirrored pair is located in a 

different expansion enclosure. This enables you to have more than 

two physical disks in the disk group within the same expansion 

enclosure. 
For example, if you are creating a six physical disk, disk group (three-

mirrored pairs), you could achieve enclosure loss protection with only 

two expansion enclosures by specifying that the physical disk in each 

mirrored pair are located in separate expansion enclosures. This 

example shows this concept:

• Mirror pair 1—Physical disk in enclosure 1 slot 1 and physical disk in 

enclosure 2 slot 1.

• Mirror pair 2—Physical disk in enclosure 1 slot 2and physical disk in 

enclosure 2 slot 2.

• Mirror pair 3—Physical disk in enclosure 1 slot 3and physical disk in 

enclosure 2 slot 3.

Because a RAID level 1 disk group requires a minimum of two physical 

disks, enclosure loss protections cannot be achieved if your storage 

array has less than two expansion enclosures.

RAID level 0 RAID level 0 does not have consistency, you cannot achieve enclosure 

loss protection.

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