Specifications

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Compaq HSG80 Array Controller ACS Version 8.4 Configuration and CLI Reference Guide
Mirrorset Switches
You can enable the following switches to control how a mirrorset behaves to ensure
data availability:
■ Replacement policy
■ Copy speed
■ Read source
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 the 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 most closely matches the size of the
remaining, operational disk drives. If more than one disk drive meets this
criterion, this switch selects the 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.
Copy Speed
Specify a copy speed to determine the speed with which the controller copies the data
from an operational disk drive to a replacement disk drive:
■ COPY=NORMAL (default) balances the overall performance of the subsystem
against the need for reconstructing the replacement disk drive.