HP Surestore Disk Array FC60 HP SureStore E Disk Array 12H User's and Service - Page 89

Concepts and Management Disk Array Features Auto Include The Auto Include feature of the disk array simplifies the process of adding new disks to your array. New disk capacity can be added to the disk array while it is running, eliminating the need to bring the host computer system down. You avoid the time consuming backup/restore process required by some disk arrays when adding new capacity. Auto Include automatically adds new disks to the disk array configuration as soon as they are installed in the array enclosure. Once included, the array immediately begins using the new disk to increase performance by adding its capacity to the RAID 0/1 space. You can continue to use the new disk to increase performance, or you can make the capacity of the new disk available to the operating system by creating a new logical drive, which is also done online without disrupting array operation. Auto Include is performed only for new disks which are operating normally and are ready to be used. Such disks typically are assigned a state of Normal when they are installed. If the disk array determines that the new disk has one of the following states, the disk will not be included automatically: • Previously Used - to protect any data that may be on the disk, you must manually add a disk with this state. • Unsupported - the disk has not been tested and certified for operation in the disk array. Only supported disks are guaranteed to work properly in the disk array. You can include an unsupported disk manually, but there is no assurance that it will operate properly in the disk array. • Failed - the disk is not functional and cannot be included, even manually. • Initialization Failed - the disk failed the initialization test performed by the controller and cannot be included, even manually. Active Hot Spare The Active Hot Spare feature of the disk array offers increased protection against disk failure. Active Hot Spare, used in conjunction with Auto Rebuild, ensures that the disk array can restore data redundancy and performance as quickly as possible following a disk failure. Active Hot Spare reserves capacity to perform a rebuild in the event of a disk failure. If you are using disks of different capacities in your array, Active Hot Spare reserves enough space to rebuild the largest disk drive. Like logical drives, the capacity reserved for the Active Hot Spare is distributed across all the disks in the array-no one physical disk contains the Active Hot Spare. Active Hot Spare is similar to the dedicated "hot spare" disks used in some conventional disk arrays. However, unlike conventional disk arrays that let the hot spare remain idle until it is needed, the disk array uses the Active Hot Spare for RAID 0/1 storage until the spare is needed. This provides the added benefit of enhancing performance while also protecting against disk failure. 89 Concepts