Sonnet Technologies Web Management Tool - Manual (Page 76)

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RAID Level 1: Mirroring (Duplicate Drives)
RAID Level 1 ensures the security of data by writing the
exact same data simultaneously to two different drives. With
RAID Level 1, the host sees what it believes to be a single
physical drive of a specific size: it does not know about the
mirrored pair. This application is used for critical data which
cannot be at risk to be lost or corrupted due to the failure of
a single drive. See
Figure B-3.
The Fusion RX1600Fibre supports an even number of 2 to 16
drives per RAID Level 1 group.
RAID Level 1 Plus Additional Mirroring
RAID Level 1 with multiple mirrors uses at least 3 drives
with the same data on each drive. This application offers the
highest fault-tolerance with good performance, especially for
small database applications. See
Figure B-4.
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. See
Figure B-5.
The Fusion RX1600Fibre supports an even number of 4 to 16
drives per RAID Level 1+0 group.
Appendix B - RAID Group Designs
Disk 1
Data 1
Data 2
Data 3
Disk 2
Data 1
Data 2
Data 3
RAID Level 1: Mirroring (Duplicate Drives)
Figure B-3
RAID Level 1 Plus Additional Mirroring
Disk 1
Data 1
Data 2
Data 3
Disk 2
Data 1
Data 2
Data 3
Disk 3
Data 1
Data 2
Data 3
Figure B-4
Disk 1
Data 1
Data 3
Data 5
Stripe 1
Stripe 2
Stripe 3
Disk 2
Data 1
Data 3
Data 5
Disk 3
Data 2
Data 4
Data 6
Disk 4
Data 2
Data 4
Data 6
RAID Level 1+0:
Striping, Mirror Spans Two Drives
Figure B-5