User guide

Array Configuration Utility (ACU)
94 Modular SAN Array 1000 User Guide
■ In RAID 5 configurations, keep the risk of logical drive failure low by
assigning no more than 14 physical drives to the array.
Each time you add a physical drive to the array, the configuration view is
updated to show how much free space remains on the array.
4. Click Next when you have finished adding physical drives to the array.
5. If an unassigned physical drive of the appropriate capacity is available, the
ACU asks you whether you want to assign spare drives to the array.
■ If you do not want this array to have a spare, click No and click Next.
■ To assign spare drives to the array, click Ye s and click Next.
On the next screen, select the drives that you want to be the spares and
click Next.
Note: 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 RAID5 configuration suffers irretrievable data loss if
two physical drives fail, regardless of the number of spare drives assigned.
Note: A spare drive can be shared by several arrays.
6. Click Finish to confirm the configuration.
230941-005_MSA1000_UG.book Page 94 Thursday, April 17, 2003 5:53 PM