HSG80 ACS Solution Software Version 8.7 for Compaq OpenVMS Installation and Configuration Guide

Planning Storage Configurations
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Configuration Guide
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• DESTROY (default) overwrites the user data and forced-error metadata when a
disk drive is initialized.
• NODESTROY preserves the user data and forced-error metadata when a disk drive
is initialized. Use NODESTROY to create a single-disk unit from any disk drive
that has been used as a member of a mirrorset. See the
REDUCED command in the
StorageWorks HSG80 Array Controller ACS Version 8.7 CLI Reference Guide
for information on removing disk drives from a mirrorset.
NODESTROY is ignored for members of a RAIDset.
Geometry
The geometry parameters of a storageset can be specified. The geometry switches are:
• CAPACITY—the number of logical blocks. The range is from 1 to the maximum
container size.
• CYLINDERS—the number of cylinders used. The range is from 1 to 16777215.
• HEADS—the number of disk heads used. The range is from 1 to 255.
• SECTORS_PER_TRACK—the number of sectors per track used. The range is
from 1 to 255.
Specifying Unit Switches
Several switches control the characteristics of units. The unit switches are described
under the
SET unit-number command in the StorageWorks HSG80 Array Controller ACS
Version 8.7 CLI Reference Guide.
One unit switch, ENABLE/DISABLE_ACCESS_PATH, determines which host
connections can access the unit, and is part of the larger topic of matching units to
specific hosts. This complex topic is covered in the first Chapter under the following
heading:
• “Determining Connections,” page 1–9
• “Assigning Unit Numbers,” page 1–11
Creating Storage Maps
Configuring a subsystem will be easier if you know how the storagesets, partitions,
and JBODs correspond to the disk drives in your subsystem. You can more easily see
this relationship by creating a hardcopy representation, also known as a storage map.