Ranges Of Disk Array Expansion - Promise VTRAK M610i Product Manual

Ranges of Disk Array Expansion

The Windows 2000 and XP (32-bit) operating systems support a 10-byte LBA
format. As a result, these OSes can only recognize 4 billion addresses. If you
create a logical drive using the default 512 B sector size, the logical drive will be
limited to 2 TB of data, even if there is more space available on your disk drives.
This limitation does not apply to Windows XP (64-bit), 2003 Server, Vista, and
Linux OSes with the 2.6 kernel. Linux OSes with the 2.4 kernel do not support
variable sector sizes, therefore you cannot apply the solution described here to
those OSes.
For Windows 2000 and XP (32-bit) operating systems, you can direct WebPAM
PROe to expand a logical drive beyond the maximum 2 TB expansion size. When
the expansion is finished:
• WebPAM PROe will show the logical drive in the desired size.
• Your operating system might show the logical drive at 2 TB.
• Additional capacity might appear as unpartitioned and unformatted.
At this point, you can format the unpartitioned/unformatted capacity as a second
logical drive.
• The Target disk array may require more disk drives than the
Source disk array
• If the Target disk array requires an EVEN number of disk
drives but the Source disk array has an ODD number, ADD a
disk drive as part of the migration process
• You cannot reduce the number of disk drives in your disk
array, even if the Target disk array requires fewer disk drives
than the Source disk array
• RAID 1 (mirroring) works with two drives only. Only a single-
drive RAID 0 disk array or a single-drive JBOD can migrate to
RAID 1. Other RAID Levels use too many drives to migrate
• You cannot migrate a disk array when it is Critical or
performing activities such as Synchronizing, Rebuilding, and
PDM
• You cannot migrate to or from RAID 6. You must create a new
disk array and move your data to it
Chapter 7: Technology Background
Important
237