Asus KFN5-Q/SAS - Manual (Page 108)

ASUS KFN5-Q Series 5-1
5.1 Setting up RAID
The NVIDIA ® nForce chipset comes with a built-in SATA RAID controller that
allows you to configure RAID 0, RAID 1, RAID 0+1, JBOD and RAID 5 with
SATA hard disk drives.
LSI SAS 1068 PCI-X eight-port, 3.0 Gbit/s SAS/SATA controller supports
eight additional SAS/SATA hard drives that allows you to create the
Integrated Mirror (RAID 1), Integrated Striping (RAID 0), and Integrated
Mirrored Enhanced (RAID IE) configurations.
5.1.1 RAID definitions
JBOD (Spanning) stands for Just a Bunch of Disks and refers to hard disk
drives that are not yet configured as a RAID set. This configuration stores
the same data redundantly on multiple disks that appear as a single disk on
the operating system. Spanning does not deliver any advantage over using
separate disks independently and does not provide fault tolerance or other
RAID performance benefits.
RAID 0
(Data striping) optimizes two identical hard disk drives to read and
write data in parallel, interleaved stacks. Two hard disks perform the same
work as a single drive but at a sustained data transfer rate, double that
of a single disk alone, thus improving data access and storage. Use of two
new identical hard disk drives is required for this setup.
RAID 1
(Data mirroring) copies and maintains an identical image of
data from one drive to a second drive. If one drive fails, the disk array
management software directs all applications to the surviving drive as
it contains a complete copy of the data in the other drive. This RAID
configuration provides data protection and increases fault tolerance to the
entire system. Use two new drives or use an existing drive and a new drive
for this setup. The new drive must be of the same size or larger than the
existing drive.
RAID 1-E
(Enhanced RAID 1) has a striped layout with each stripe unit
having a secondary (or alternate) copy stored on a different disk. You can
use three or more hard disk drives for this configuration.
RAID 0+1 is
data striping and data mirroring combined without parity
(redundancy data) having to be calculated and written. With the RAID
0+1 configuration you get all the benefits of both RAID 0 and RAID 1
configurations. Use four new hard disk drives or use an existing drive and
three new drives for this setup.