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ATTO Technology Inc. FastStream SC Installation and Operation Manual
RAID Level 1+0: striping, mirror spans two drives
RAID Level 1+0 increases data transfer rates while
ensuring security by writing the exact same data
simultaneously to two or more different drives.
RAID Level 1+0 is used in applications requiring high
performance and redundancy, combining the
attributes of RAID Levels 1 and 0.
The ATTO FastStream supports an even number of 4
to 16 drives per RAID Level 1+0 group.
RAID Level 4: striping, one parity drive
RAID 4 writes data across multiple drives or devices
(striping) with parity blocks written to a single drive in
the RAID Group. This increases reliability while using
fewer drives than mirroring.
RAID Level 4 is best suited for applications that
perform mostly sequential access such as video
applications.
You must have at least three drives to set up RAID
Level 4.
RAID Level 5: striping, parity distributed among drives
RAID Level 5 increases reliability while using fewer
drives than mirroring by using parity redundancy:
parity is distributed across multiple drives.
The ATTO FastStream supports 3 to 16 drives per
RAID Level 5 group.
Stripe 1
Stripe 2
Stripe 3
Data 6
Data 4
Data 2
Data 6
Data 4
Data 2
Data 5
Data 3
Data 1
Data 5
Data 3
Data 1
Disk 1
Disk 2
Disk 3
Disk 4
Stripe 2
Stripe 3
Stripe 1
Parity 7-9
Parity 4-6
Parity 1-3
Data 9
Data 6
Data 3
Data 8
Data 5
Data 2
Data 7
Data 4
Data 1
Disk 1
Disk 2
Disk 3
Disk 4
Data 12
Data 11
Data 10
Parity 10-12
Stripe 2
Stripe 3
Stripe 1
Data 8
Data 4
Parity 1-3
Data 7
Parity 4-6
Data 3
Parity 7-9
Data 6
Data 2
Data 9
Data 5
Data 1
Disk 1
Disk 2
Disk 3
Disk 4
Stripe 4