Dell PowerEdge RAID Controller 6E User Manual
Page 149
Glossary
149
Protocol
A set of formal rules describing how to transmit data, generally across a network
or when communicating with storage subsystems. Low-level protocols define
the electrical and physical standards to be observed, bit- and byte-ordering, and
the transmission and error detection and correction of the bit stream. High-level
protocols deal with the data formatting, including the message syntax, the
terminal to system dialogue, character sets, sequencing of messages, etc.
R
RAID
Acronym for Redundant Array of Independent Disks (originally Redundant
Array of Inexpensive Disks). It is 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, 6, 10, 50, and 60)
provide data protection.
RAID Level Migration
RAID level migration (RLM) changes the array from one RAID level to another.
It is used to move between optimal RAID levels. You can perform a RLM while
the system continues to run, without having to reboot. This avoids downtime
and keeps data available to users.
RAID Levels
A set of techniques applied to disk groups to deliver higher data availability,
and/or performance characteristics to host environments. Each virtual disk must
have a RAID level assigned to it.
RAID Management Utility
A RAID management utility is used to configure physical disks into disk groups
and virtual disks. The BIOS Configuration Utility is also known as Ctrl+R. Use
the BIOS Configuration Utility if no operating system has been installed yet on
the controller. The BIOS Configuration Utility 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.
Dell_PERC6.2_UG.book Page 149 Wednesday, June 24, 2009 6:08 PM