User's Manual

Configuring an Array
HP Smart Array 641/642 Controller User Guide 5-9
HP CONFIDENTIAL
Writer: John Turner File Name: f-ch5 configuring an array
Codename: darkmatter - antimatter Part Number: 309311-001 Last Saved On: 11/6/02 4:17 PM
Adding Spare Drives
To add spare drives to an array, the array controller must have at least one attached
drive that is unassigned, or is assigned as a spare to another array.
You can:
• Assign a different online spare to each array on the controller.
• Share one online spare among several arrays on the same controller, for efficient
use of drive capacity.
• Assign several online spares to just one array.
• Share several online spares among several arrays; this method provides the
greatest amount of protection for the largest number of arrays.
IMPORTANT: Assigning several spares to an array lets you postpone replacement of faulty
drives, but it does not increase the fault-tolerance level of any logical drives in the array. For
example, a logical drive in a RAID 5 configuration suffers irretrievable data loss if two physical
drives fail simultaneously, regardless of the number of spare drives assigned.
Any drive that you assign as an online spare for an array operates as the spare for
every fault-tolerant logical drive within that array.
When you select Assign Spare, only drives that qualify are displayed; for example,
drives with too small a capacity are not listed. If a drive that you expect to see is not
listed, press the Tab key (to switch to the physical drive view) and check the capacity
of the drive.
To add a spare:
1. In the Logical Configuration View panel, highlight the array that needs a spare,
and then press the Enter key.
2. Choose Assign Spare in the Array Options menu, and then press the Enter key.
3. Select the drive that you want as the spare, and then press the Enter key.
4. Press the Esc key to accept the new configuration and return to the main manual
configuration screen.