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Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide
RAIDset Switches
You can enable the following switches to control how a RAIDset behaves to ensure
data availability:
■ Replacement policy
■ Reconstruction policy
■ Membership
Replacement Policy
Specify a replacement policy to determine how the controller replaces a failed disk
drive:
■ POLICY=BEST_PERFORMANCE (default) puts the failed disk drive in the
failedset, then tries to find a replacement (from the spareset) that is on a different
device port than the remaining operational disk drives. If more than one disk
drive meets this criterion, this switch selects a drive that also provides the best fit.
■ POLICY=BEST_FIT puts the failed disk drive in the failedset, then tries to find a
replacement (from the spareset) that equals or exceeds the base member size
(smallest disk drive at the time the RAIDset was initialized). If more than one
disk drive meets this criterion, this switch selects one that also provides the best
performance.
■ NOPOLICY puts the failed disk drive in the failedset and does not replace it. The
storageset operates with less than the nominal number of members until you
specify a replacement policy or manually replace the failed disk drive.
Reconstruction Policy
Specify the speed with which the controller reconstructs the data from the remaining
operational disk drives and writes it to a replacement disk drive:
■ RECONSTRUCT=NORMAL (default) balances the overall performance of the
subsystem against the need for reconstructing the replacement disk drive.