system. The PERC Virtual Disk Management utility, accessed by pressing <Ctrl><R> at system startup, is built on elements called controls. Each control performs a function. The functions include procedures you can use to configure physical disks and virtual disks. The PERC Virtual Disk Management utility differs from the Dell Inc. system BIOS, which contains the BIOS settings for each Dell platform and is accessed by pressing <F2> during system startup.
P H YS I C A L DI S K — A
P N P (P L U G A N D P L A Y ) — A technology that allows automatic recognition of interface cards and devices when plugged into a PC.
P O R T — A connection point to a RAID controller, disk drive, enclosure, or another device.
RAID (R E D U N D A N T A R R A Y O F I N D E P E N D E N T D I S K S ) — An array of multiple independent physical disks managed together to yield higher reliability and/or performance exceeding that of a single physical disk. The virtual disk appears to the operating system as a single storage unit. I/O is expedited because several disks can be accessed simultaneously. Redundant RAID levels (RAID levels 1, 5, and 10) provide data protection.
RAID L E V E L S — A set of techniques applied to the physical disks in a virtual disk to deliver higher data availability, and/or performance characteristics to host environments. Each virtual disk must have a RAID level assigned to it.
RAID M A N A G E M E N T U T I L I T Y — A RAID management utility (PERC Virtual Disk Management utility) is used to configure physical disks and virtual disks. Use the PERC Virtual Disk Management utility if the operating system has not yet been installed on the controller.
R E B U I L D — The regeneration of all data to a replacement disk in a redundant virtual disk (RAID levels 1, 5, and 10) after a physical disk failure. A disk rebuild normally occurs without interrupting normal operations on the affected virtual disk, though some degradation of performance of the disk subsystem can occur.
R E D U N D A N C Y — The provision of multiple interchangeable components to perform a single function to cope with failures and errors. Common forms of hardware redundancy are disk mirroring, implementations of parity disks, or distributed parity.
R E D U N D A N T VI R T U A L D I S K — A redundant virtual disk is one which has redundant data on physical disks that can be used to rebuild a failed physical disk. A virtual disk can use disk striping across the physical disks, disk mirroring or parity to provide redundancy. This offers protection in case of a physical disk failure.
R E P L A C E M E N T D I S K — A physical disk that replaces a failed physical disk in a virtual disk.
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Glossary
