INTRODUCTION
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In the illustration, volume 1 can be assigned a RAID level 5 of
operation while volume 0 might be assigned a RAID level 1E of
operation. Alterantively, the free space can be used to create vol-
ume 2, which could then be set to use RAID level 5.
1.3.3 Ease of Use Features
1.3.3.1 Foreground Availability/Background Initial-
ization
RAID 0 and RAID 1 volume sets can be used immediately af-
ter creation because they do not create parity data. However,
RAID 3, 5 and 6 volume sets must be initialized to generate
parity information. In Backgorund Initialization, the initializa-
tion proceeds as a background task, and the volume set is fully
accessible for system reads and writes. The operating system
can instantly access the newly created arrays without requir-
ing a reboot and without waiting for initialization to complete.
Furthermore, the volume set is protected against disk failures
while initialing. If using Foreground Initialization, the initializa-
tion process must be completed before the volume set is ready
for system accesses.
1.3.3.2 Array Roaming
The SATA RAID controllers store RAID conguration information
on the disk drives. The controller therefore protect the congu-
ration settings in the event of controller failure. Array roaming
allows the administrators the ability to move a completele RAID
set to another system without losing RAID conguration infor-