User manual
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APPENDIX
In the illustration, volume 1 can be assigned a RAID level 5 of
operation while volume 0 might be assigned a RAID level 10 of
operation. Alternatively, the free space can be used to create vol-
ume 2, which could then be set to use RAID level 5.
Ease of Use Features
• Foreground Availability/Background Initialization
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 background 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.
• Online Array Roaming
The SATA RAID controllers store RAID conguration information
on the disk drives. The controller therefore protects the congu-
ration settings in the event of controller failure. Array roaming
allows the administrators the ability to move a completed RAID
set to another system without losing RAID conguration infor-
mation or data on that RAID set. Therefore, if a server fails, the
RAID set disk drives can be moved to another server with an
Areca RAID controller and the disks can be inserted in any order.
• Online Capacity Expansion
Online Capacity Expansion makes it possible to add one or more
physical drives to a volume set without interrupting server op-
eration, eliminating the need to backup and restore after recon-
guration of the RAID set. When disks are added to a RAID set,
unused capacity is added to the end of the RAID set. Then, data