DELL MD3220 사용자 설명서

Planning: MD3200 Series Storage Array Terms and Concepts

3 Provide host server access.
4 Create mappings to associate the virtual disks with the host servers. 

Host server access must be created before mapping virtual disks.

Disk groups are always created in the unconfigured capacity of a storage array. 

Unconfigured capacity is the available physical disk space not already 

assigned in the storage array.
Virtual disks are created within the free capacity of a disk group. Free capacity 

is the space in a disk group that has not been assigned to a virtual disk.

The storage array recognizes the following virtual disk states.

RAID levels determine the way in which data is written to physical disks. 

Different RAID levels provide different levels of accessibility, redundancy, and 

capacity.

Optimal

The virtual disk contains physical disks that are all online.

Degraded

The virtual disk with a redundant RAID level contains an inaccessible 

physical disk. The system can still work properly, but performance may 

be affected and additional disk failures may result in data loss.

Offline

A virtual disk with one or more member disks in an inaccessible 

(failed, missing, or offline) state. Data on the virtual disk is no longer 

accessible.

Force online The storage array forces a virtual disk that is in an Offline state to an 

Optimal state. If all the member physical disks are not available, the 

storage array forces the virtual disk to a Degraded state. The storage 

array can force a virtual disk to an Online state only when a sufficient 

number of physical disks are available to support the virtual disk.

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