AMCC 3ware 9000 Series, User Manual

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3ware Disk Manager (3DM 2)
62 3ware 9000 Series Serial ATA RAID Controller User Guide
Rebuild Unit. Replaces a degraded drive in a degraded unit with an available
drive and begins rebuilding the RAID. When you select a degraded unit and
click
Rebuild Unit , a dialog box listing available drives appears, so that you
can select the drive you want to use. If the degraded unit has more than one
degraded drives (for example, a RAID 10 where both mirrored pairs each
have a degraded drive), you will repeat this process a second time.
If rebuild scheduling is enabled on the Scheduling page, the unit will not start
actively rebuilding until the scheduled time, and the status will change to say
“Rebuild-Paused.” (The Unit Details page indicates whether a unit is actively
rebuilding.) If rebuild scheduling is not enabled, the rebuild process will
begin right away.
For more information about rebuilds, see “About Rebuilds” on page 121.
Migrate Unit. Reconfigures a unit while it is on-line. Migration can be used to
change only the RAID level, to expand the capacity by adding additional
drives, or to change the stripe size.
Caution:
Once migration of a unit is started, it cannot be cancelled.
When you select a unit and click Migrate Unit , a dialog box appears which
lists the drives in the unit and any additional available drives. In the dialog
box are two drop-down menus, one for choosing the RAID level and one for
choosing stripe size.
You can only migrate a unit to a RAID level that will be larger than the
original unit. For example, you can migrate from a RAID 5 array with 4
drives to a RAID 0 with four drives but you cannot migrate from a RAID 5
with four drives to a RAID 10 with four drives.
After you have specified changes to the unit, the Unit Maintenance screen
reflects your changes and shows the percentage of migration completed.
While the unit is migrating, you can still access the unit as normal but the
performance will be lower. You can adjust the I/O rate with the radio buttons
on the Controller Settings page.
For more information, see “About Migration” on page 123.