HP 2000fc Hp StorageWorks 2000 Family Modular Smart Array CLI reference guide - Page 264

data mirroring data striping DHCP direct attach storage (DAS) disk mirroring drive enclosure drive module dynamic spare EC EMP enclosure Data written to one disk drive is simultaneously written to another disk drive. If one disk fails, the other disk can be used to run the virtual disk and reconstruct the failed disk. The primary advantage of disk mirroring is 100 percent data redundancy: since the disk is mirrored, it does not matter if one of the disks fails; both disks contain the same data at all times and either can act as the operational disk. The disadvantage of disk mirroring is that it is expensive because each disk in the virtual disk is duplicated. RAID 1 and 10 use mirroring. The storing of sequential blocks of incoming data on all the different disk drives in a virtual disk. This method of writing data increases virtual disk throughput because multiple disks are working simultaneously, retrieving and storing. RAID 0, 3, 5, 6, 10, and 50 use striping. Dynamic Host Configuration Protocol. A dedicated storage device that connects directly to one or more servers. (SNIA) Supported for the MSA2012fc. See data mirroring. An enclosure that contains disk drives and one or two expansion modules. Drive enclosures can be attached to a controller enclosure to provide additional storage capacity. See expansion module. A FRU consisting of a disk drive and drive sled. An available disk drive that is used to replace a failed drive in a virtual disk, if the Dynamic Spares feature is enabled and no vdisk spares or global spares are designated. See Expander Controller (EC). See enclosure management processor (EMP). A physical storage device that contains disk drives. If the enclosure contains integrated RAID controllers it is known as a controller enclosure; otherwise it is a drive enclosure. 264 HP StorageWorks 2000 Family Modular Smart Array CLI reference guide • May 2008