Datasheet

Glossary-3

Glossary

clear

Foreground initialization of a fault-tolerant array. A clear operation

zeros all blocks of the array. The array is not accessible until the

clear task is complete.

concatenation

Joining of physical or logical drives in sequential order.

consistency check command

The controller continuously performs a verification on a redundant

array to data integrity. In the case of RAID 1 or 10, consistency

checks assure that the data between like blocks match. In the case

of a RAID 5, consistency checks assure that data in the stripe and

the calculated parity for the stripe match.

container

See array.

dead partition

See failed.

degraded

A redundant (for example, a RAID 1) array in which one or more

members have failed. The data is intact but redundancy has been

compromised. Any further failure would cause the array to fail and

result in data loss.

dirty data

Data that has been written to a cache but which has not been

“flushed” out to its final destination.

disk drive

Device for storing non-removable, rewritable media. See also hard

disk, hard drive.

disk ID

Unique disk identifier that consists of the channel number, ID, and

LUN (channel:ID:LUN), for example, 1:04:0. See also channel.