MicroNet Technology RAIDBank4 manual Understanding RAID

2-Understanding RAID

Chapter 2. Understanding RAID

The RAIDBank4 controller subsystem is a high-performance SATA2 drive bus disk array controller. When properly configured, the RAIDBank4 can provide non-stop service with a high degree of fault tolerance through the use of RAID technology and advanced array management features.

The RAIDBank4 can be configured to RAID levels 0, 1, 10, 3, and 5, as well as disk spans and direct mapping. RAID levels other than 0 are able to tolerate a hard disk failure without impact on the existing data, and failed drive data can be reconstructed from the remaining data and parity drives. RAID configuration and monitoring is accessible through the LCD front control panel or the built in web administration interface. The RAIDBank4 features the following high availability functions:

•RAID Levels 0,1,10,3,5, disk spans, and direct mapping Support

•Up to 4 discrete LUN support

• Online Capacity Expansion	FYI:
	The Berkeley RAID levels are a family of
• Online RAID Level Migration
	disk array data protection and mapping
• Logical Drive Capacity Extension
	techniques described by Garth Gibson, Randy Katz,
• Array Roaming
	and David Patterson in papers written while they
• Automatic Drive Failure Detection	were performing research into I/O subsystems at
• Automatic Failed Drive Rebuilding	the University of California at Berkeley. There are
• Hot Spare Disk Drives	six Berkeley RAID Levels, usually referred to by the
	names RAID Level 1, etc., through RAID Level 6.
• Instant Availability/Background Initialization.

This section will help you gain understanding of how these functions can serve your needs best.

RAID

RAID is an acronym for Redundant Array of Independent Disks. It is an array of multiple independent hard disk drives that provide high performance and fault tolerance through support of several levels of the Berkeley RAID techniques. An appropriate RAID level is selected when the volume sets are defined or created, and is based on disk capacity, data availability (fault tolerance or redundancy), and disk performance considerations. The RAIDBank4 controller makes the RAID implementation and the disks’ physical configuration transparent to the host operating system, which means that the host operating system drivers and software utilities are not affected regardless of the RAID level selected.

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