Compaq HSZ80 manual RAIDset Switches, Replacement Policy, Reconstruction Policy

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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.

Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide