Asus DS300j G2 Series User Manual page 193

Mirror + Stripe combines both of the RAID 1 and RAID 0 logical drive types. RAID 10 can increase performance
by reading and writing data in parallel or striping, and duplicating the data, or mirroring.
ASUS Storage implements RAID 10 by creating a data stripe over one pair of disk drives, then mirroring the
stripe over a second pair of disk drives. Some applications refer to this method as RAID 0+1
The data capacity RAID 10 logical drive equals the capacity of the smallest physical drive times the number of
physical drives, divided by two.
In some cases, RAID 10 offers double fault tolerance, depending on which physical drives fail.
RAID 10 arrays require an even number of physical drives and a minimum of four.
For RAID 10 characteristics using an odd number of physical drives, choose RAID 1E.
Advantages
• Implemented as a mirrored disk array whose
segments are RAID 0 disk arrays
• High I/O rates due to multiple stripe segments
Recommended Applications for RAID 10:
• Imaging applications
• Database servers
• General fileserver
rAid 30 – s d P
triPing of edicAted Arity
RAID 30 combines both RAID 3 and RAID 0 features. Data is striped across physical drives as in RAID 0, and it
uses dedicated parity as in RAID 3. RAID 30 provides data reliability, good large file read, and high transfer rate
performance.
Component Minimum
Number of Axles 2
Physical Drives per Axle 3
Physical Drives per Logical Drive 6
rAid 30 A
xles
When you create a RAID 30 you must specify the number of axles. An axle refers to two or more RAID 3 logical
drives striped together to make a RAID 30. An axle can have from 3 to 32 physical drives, depending on the
number of physical drives in the logical drive. The chart below shows RAID 30 logical drives with 6 to 16 physical
drives, the available number of axles, and the resulting distribution of physical drives on each axle.
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Disadvantages
• Very high disk overhead – uses only 50% of total
capacity
Maximum
16
32
256
Drives
No. of
No. of Drives per No. of Drives
Axles
Axle
6 2 3,3 14
7 2 3,4
8 2 4,4
9 2 4,5 15
3 3,3,3
10 2 5,5
3 3,3,4
11 2 5,6 16
3 3,4,4
12 2 6,6
3 4,4,4
4 3,3,3,3
13 2 6,7
3 4,4,5
4 3,3,3,4
Advantages
• Good for large files with high transfer
rates where fault tolerance is also
required
Recommended Applications for RAID 30:
• Video editing
• Multimedia production
• File and application server
rAid 50 – s d P
triPing of istributed Arity
RAID 50 combines both RAID 5 and RAID 0 features. Data is striped across physical drives as in RAID 0, and
it uses distributed parity as in RAID 5. RAID 50 provides data reliability, good overall performance, and supports
larger volume sizes.
The data capacity RAID 50 logical drive equals the capacity of the smallest physical drive times the number of
physical drives, minus two.
RAID 50 also provides very high reliability because data is still available even if multiple physical drives fail (one
in each axle). The greater the number of axles, the greater the number of physical drives that can fail without
DS300f G2 Series User Manual
No. of Axles Drives per Axle
2 7,7
3 4,5,5
4 3,3,4,4
2 7,8
3 5,5,5
4 3,4,4,4
5 3,3,3,3,3
2 8,8
3 5,5,6
4 4,4,4,4
5 3,3,3,3,4
Disadvantages
• Random write performance only fair.
Disk failure has a medium impact on
throughput