Understanding raid concepts and terminology – Audible 2220 User Manual
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Understanding RAID Concepts and Terminology
The following concepts and terminology is commonly used when describing the functions of the
Rocket RAID 2220 Host Adapter.
Disk initialization
Initializing a disk writes necessary RAID configuration information to that disk. Disks must be initialized
before configuring them into RAID arrays. The initialization process will destroy all data on the disk.
Disk Status
New
The disk contains no data and has not been initialized.
Initialized
The disk has been initialized and can be used for array creation.
Configured
The disk has been assigned to one or more arrays, or configured as a spare disk.
Legacy
The disk was used on other controllers before use with the RocketRAID 2220 (see legacy
disk below).
Array initialization
A redundant array (RAID5, RAID1, RAID10) needs to be initialized to ensure full performance and
reliability. Non-redundant arrays (RAID0, JBOD) do not need to be initialized.
When you create a redundant array using the RocketRAID 2220 controller’s BIOS Configuration Utility, it
will create the array in un-initialized state. The initialization process can be completed after installing the
driver and management software.
When creating an array using the HighPoint RAID Management Console s oftware, you can specify an
initialization option (Skip initialization, foreground and background).
Foreground initialization
Foreground initialization will zero-out all data on the array. The array is not accessible by the operating
system until initialization is complete.
Background initialization
Background initialization allows the array to be used immediately. For RAID1 and RAID10 arrays,
initialization will results in data being duplicated identically to the mirror pair. For RAID5 arrays,
initialization will result in parity being generated from all array members.
Note: An un-initialized RAID1 or RAID10 array can still provide redundancy in case of a disk failure. A
RAID5 array, however, is not fault-tolerant until initialization is finished.