# Things to consider when changing the RAID level

## ServeRAID SCSI controllers

If you have a... | And you want... | Then...
RAID level-0 array with two or more drives | RAID level-5 | Add one and only one drive
RAID level-1 array with two and only two drives | RAID level-5 | Add one and only one drive
RAID level-5 array | RAID level-0 | The ServeRAID Manager removes the last drive in the array
RAID level-5 Enhanced array | RAID level-5 | The ServeRAID Manager does not add or remove a drive

## ServeRAID SATA and SAS controllers

Note: Not all RAID level migrations are supported by all ServeRAID controllers.

If you have a... | And you want... | Then...
RAID level-0 logical drive with two or more drives | RAID level-5 | Add at least one drive
RAID level-5 logical drive | RAID level-0 | Optionally, remove one drive
RAID level-0 logical drive | RAID level-10 | Double (at least) the drive count
RAID level-6 logical drive | RAID level-5 | Optionally, remove one or two drives
RAID level-5 logical drive | RAID level-5EE | Add at least one drive
RAID level-5 logical drive | RAID level-6 | Add one or two drives (second drive may be necessary to support N data + 2 parity drives)
RAID level-5EE logical drive | RAID level-5 | Optionally, remove one drive
RAID level-5 logical drive | RAID level-10 | Make sure you have (source-1)*2 drives total
RAID level-1 logical drive | RAID level-5 | Add at least one drive
RAID level-1 logical drive | RAID level-10 | Add at least two drives

## ServeRAID Enclosures (networked storage)

If you have a... | And you want... | Then...
RAID level-0 logical drive with two or more drives | RAID level-5 | Add at least one drive
RAID level-1 logical drive | RAID level-5 | Add at least one drive
RAID level-1 logical drive | RAID level-10 | Add at least two drives in multiples of two

## More information

- Changing the RAID level (action)
- Changing the RAID level (SAS, SATA, HostRAID) (action)
- Changing the RAID level (enclosures) (action)
- Understanding logical-drive migration

Glossary | Contents

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