Raid Level Migration - Promise Technology VessRAID 1740s Product Manual

VessRAID 1740s, 1840s Product Manual

RAID Level Migration

To migrate a disk array is to do one or both:
• Change its RAID level
• Increase the number of disk drives (sometimes called Expansion)
On VessRAID, RAID level migration is performed on the disk array but it applies
to the logical drives. Migration takes place on an existing Functional disk array
without disturbing the existing data. While the disk array is migrating, you can
access the data as before. When migration is complete, your disk array will have
a different RAID level and/or a larger capacity.
In most cases, you must add one or more physical drives during the migration
process. You can never reduce the number of physical drives.
The tables below show the migration options for a source logical drive according
to its RAID level. The available target RAID levels are shown with their
requirements.
See "Migrating a Disk Array" on page 106 or page 147.
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