Chapter 4: Technology Background
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The choices are:
•
GB Truncate
– (Default) Reduces the useful capacity to the nearest
1,000,000,000 byte boundary.
•
10GB Truncate
– Reduces the useful capacity to the nearest
10,000,000,000 byte boundary.
•
Group Rounding
– Uses an algorithm to determine how much to truncate.
Results in the maximum amount of usable drive capacity.
•
Table Rounding
– Applies a predefined table to determine how much to
truncate.
Capacity coercion also affects a replacement drive used in a disk array. Normally,
when an physical drive fails, the replacement drive must be the same capacity or
larger. However, the capacity coercion feature permits the installation of a
replacement drive that is slightly smaller (within 1 gigabyte) than the remaining
working drive. For example, the remaining working drives can be 80.5 GB and
the replacement drive can be 80.3, since all are rounded down to 80 GB. This
permits the smaller drive to be used.
Without capacity coercion, the controller does not permit the use of a
replacement physical drive that is slightly smaller than the remaining working
drives.