HSG80 Array Controller ACS Version 8.2 User Guide (EK-HSG80-UG. B01, July 1998)

Creating Storagesets 3–41
Membership
Indicate to the controller that the RAIDset you are adding is either
complete or reduced, which means it is missing one of its members:
NOREDUCED (default) indicates to the controller that all of the
disk drives are present for a RAIDset.
REDUCED lets you add a RAIDset that is missing one of its
members. For example, if you dropped or destroyed a disk drive
while moving a RAIDset, you could still add it to the subsystem by
using this switch.