Specifications

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ATTO Technology Inc. FastStream SC Installation and Operation Manual
Appendix B Design RAID Groups
The ATTO FastStream provides instant hardware data protection and intelligence to existing storage independent
of the storage type.
CAUTIONCAUTION
RAID improves data accessibility and
reliability during normal operations,
however, you still need a good backup
strategy for long-term protection of your
data.
To set up RAID groups refer to Configure Storage
into RAID Groups on page 11.
The ATTO FastStream allows RAID functionality. In
general, the process begins with individual drives
called block devices.
Note
If a drive has corrupt or outdated configuration
data, that drive cannot be assigned to any
RAID group. Ensure all drives are configured
properly. Refer to
Initialize Drives on page 9
or
Eliminating RAID configuration data on
page 27.
A RAID group is a virtual, independent single drive
whose data is written to physical drives according to a
RAID algorithm. The ATTO FastStream supports
JBOD, DVRAID, RAID Level 0, RAID Level 1, RAID
Level 1+ 0, RAID Level 4 and RAID Level 5.
RAID improves data accessibility and reliability during
normal operations, however, you still need a good
backup strategy for long-term protection of your data.
JBOD (Just a Bunch of Disks)
JBOD (Just a Bunch of Disks) configuration allows
many individual drives to be available for normal
storage operations with no special data protection by
combining several drives into one large drive. A
special case of a RAID group, multiple physical drives
are assigned to a JBOD RAID group and their storage
areas appear as a single spanned area of storage.
The ATTO FastStream supports 1 to 32 drives per
JBOD-configured RAID group.
Exhibit A-2 JBOD: Just a Bunch of Disks: no
redundancy; each disk is treated independently
DVRAID (Digital Video RAID)
Digital Video RAID provides parity redundancy for
your data. Optimized for performance for the high data
transfer rates required in digital video environments,
DVRAID is ATTO Technology proprietary technology
which supports the editing of uncompressed 10-bit
High Definition (HD) video and multiple streams of
real-time, uncompressed Standard Definition (SD)
video.
You must use the Quick Digital Video setup wizard in
the ExpressNAV Storage Manager.
RAID Level 0
RAID Level 0 (striping) is based on the fact that
increased performance can be achieved by
simultaneously accessing data across multiple drives,
increasing data transfer rates while reducing average
access time by overlapping drive seeks. Drives are
accessed alternately, as if stacked one on top of the
other. RAID Level 0 provides no data protection. If one
drive fails, all data within that stripe set is lost.
RAID Level 0 is used by applications requiring high
performance for non-critical data.
The ATTO FastStream supports 2 to 16 drives per
RAID Level 0 group.
Exhibit A-3 RAID Level 0, no redundancy
JBOD
Disk 0 Disk 1 Disk 2
D0 D4 D8
D1 D5 D9
D2 D6 D10
D3 D7 D11
RAID Level 0
Stripe Disk 0 Disk 1 Disk 2 Disk 3
0 D0D1D2D3
1 D4D5D6D7