HP Workstation xw8000 - Manual (Page 42)

3-10
Adaptec SCSI RAID 2120S/2200S Software User’s Guide
View
is the default display mode and when expanded, will show the
following information about each device:
■ Capacity of the drive
■ Drive manufacturer and model number
■ SCSI drive ID
When expanded, the Full Size Capacity View button and the
Relative Size Capacity View button represent each drive as a
bar. A drive that is not used as part of any array is shaded blue
surrounded by a dotted line.
displays a full-length bar for each drive, regardless of capacity.
displays a bar for each drive, with the largest capacity drive
full-length and the other drives proportional to the drive capacity,
relative to the largest drive.
Any part of a drive used in an array is shown as a gray segment
within the bar. Selecting any gray segment will highlight it in
amber and, in the Logical Devices view, highlight the array of
which this segment is a member.
In either the Full Size Capacity View or the Relative Size Capacity
View
, a small portion at the end of the drive is shown in dark gray.
The segment at the end of the drive may vary in size from drive to
drive because, in addition to the RAID signature, the controller
also limits the usable capacity of each drive to increments of 100
MB.
This is done because hard disk drives of apparently the same
capacity from different manufacturers, or even different models
from the same manufacturer, actually vary slightly in the true
capacity available. Although, in normal operation this is not an
issue, it can be when assigning hot spares or replacing a failed
drive.
If the controller used the maximum capacity of each drive and a
hot spare or replacement drive was just a few megabytes smaller, it
would not be able to replace the failed drive. By rounding drive
capacities down to the nearest 100 MB, this possibility is effectively
eliminated.
UG.book Page 10 Saturday, October 26, 2002 12:08 PM