HP StorageWorks HSG80 ACS Solution Software V8.8 for Linux X86 Installation and Configuration Guide (AA-RV1LA-TE, March 2005)

Planning Storage Configurations
60 HSG80 ACS Solution Software V8.8 for Linux X86 Installation and Configuration Guide
Tip: If you are redeploying disks that have been operating under a prior version of
ACS into a newly established container, as a best practice,
always initialize the
devices and the new container before proceeding with subsystem activities to avoid
operational and performance issues.
Configuring Large Storagesets
When creating large storagesets, the logical geometry presented by the array
controller may be outside the limits of the operating system. When this occurs,
your storageset is reported by the operating system as having a smaller size than is
correct.
If one of your storagesets is significantly smaller than you expect, the operating
system may be reporting the logical geometry of the storageset incorrectly. One of
the more common instances of this phenomenon occurs when the cylinder count
exceeds 65535, which causes it to “wrap around.” This problem can be easily
remedied by bringing the logical geometry, as presented by the controller, within
the bounds of the operating system. To bring the logical geometry within bounds,
use the ACS
INITIALIZE command with the appropriate combination of the
CYLINDERS, HEADS and SECTORS_PER_TRACK qualifiers.
The following example shows the steps to take:
1. Note the size and geometry information of the storageset using the
SHOW
unit-number
command.
HSG80> SHOW D101
Executing this command reports the size (in blocks) and geometry of the
storageset. For example:
Note that the geometry values may be rounded, so that the formula:
cylinders x heads x sectors
may not yield the exact number for the size in blocks. When performing
calculations, always ensure that the product of the above formula is no greater
than the original size of the storageset in blocks (i.e., make sure that the
logical geometry is no greater than the physical geometry).
Size: 80913640
Geometry (C/H/S): 74983 / 20 / 254