Changing RAID Level

You can use migrate to change the RAID level of an existing unit while the unit is online, without experiencing any data loss. When you change a RAID level, you may also add one or more drives to the unit. You can also migrate to change the unit's stripe size. For example, a four-drive RAID 5 with a 64KB stripe size can be migrated to a four-drive RAID 5 with 256KB stripe size. The steps below describe how to change a RAID level in 3DM2.

Note: Once migration starts, the unit stays in the migrating state until the migration process is complete. The migration process cannot be aborted, and must be allowed to finish before a rebuild or verify to the unit is permitted.

Warning: It is important that you allow migration to complete before adding to the unit. Making physical changes to the unit during migration may cause the migration process to stop, and can jeopardize the safety of your data.

To change the RAID level of a unit

In 3DM 2, choose Management > Maintenance.

In the Unit Maintenance table on the Maintenance Page, select the unit for which you wish to change the RAID level, by checking the box next to the Unit ID.

Click the Migrate Unit button.

The Migrate dialog box appears.

Select any drives to be added to the unit.

Select the new RAID level.

Optionally, select a new Stripe size.

Click OK.

The Maintenance page updates to show the new unit and the Migration progress.

Inform the operating system of the change, as described under Informing the Operating System of Changed Configuration

Note: You can only migrate a unit to a RAID level that has the same or more capacity as the existing one. A four-drive RAID 5 unit can migrate to a four- drive RAID 0, but a four-drive RAID 0 unit cannot migrate to a four-drive RAID 5, without adding another drive, due to the need for additional storage capacity for parity bits.

Changing RAID Level

To change the RAID level of a unit

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