Chapter 6: Managing Logical Drives and Hot Spares ● 74Working with Hot SparesA hot spare is a disk drive that automatically replaces any failed drive in a logical drive, and cansubsequently be used to rebuild that logical drive. (For more information on recovering from adisk drive failure, see page 116.)Hot Spare Limitations● You can’t create a hot spare for RAID 0 logical drives, simple volumes, or spanned volumes.● You can’t create a hot spare from a disk drive that is already part of a logical drive.● You should select a disk drive that is at least as big as the largest disk drive it might replace.Dedicated Spare or Global Spare?A global hot spare is not assigned to a specific logical drive and will protect any logical drive onthe controller (except RAID 0 logical drives). You can designate a global hot spare before orafter you build logical drives on a controller; you can also designate a global hot spare whileyou’re creating a logical drive. To designate a global hot spare, see the following section.A dedicated hot spare is assigned to one or more specific logical drives and will only protectthose logical drives. You must create the logical drive before you can assign a dedicated hotspare. To assign a dedicated hot spare, see page 75.Designating a Global Hot SpareThis section describes how to designate a global hot spare before or after you build a logical drive.Note: To designate a global hot spare while you’re creating a logical drive, see Step 6 on page 44.To designate a global hot spare:1 In the Enterprise View, click the controller on which you want a global hot spare.2 In the Physical Devices View, click the disk drive you want to designate as a hot spare. (SeeHot Spare Limitations for help selecting a disk drive.)3 Click the Create global hot-spare drive button (shown at right).A plus sign appears beside the selected disk drive, indicating that it’s designated as a hotspare. (A yellow plus sign indicates an error. See What Do the Hot Spare Icons Mean? onpage 76 for help solving the problem.)Any other logical drives created on the controller will automatically be protected by thatglobal hot spare.Hot spare
