Planning: MD3200i Series Storage Array Terms and Concepts 41
Each RAID level provides different performance and protection. You should
select a RAID level based on the type of application, access, fault tolerance,
and data you are storing.
The storage array supports RAID levels 0, 1, 5, 6, and 10. The maximum
number of physical disks that can be used in a disk group depends on the
RAID level:
• 96 for RAID 0, 1 and 10
• 30 for RAID 5 and 6.
RAID Level Usage
To ensure best performance, you should select an optimal RAID level when
you create a system physical disk. The optimal RAID level for your disk array
depends on:
• Number of physical disks in the disk array
• Capacity of the physical disks in the disk array
• Need for redundant access to the data (fault tolerance)
• Disk performance requirements
RAID 0
RAID 0 uses disk striping to provide high data throughput, especially for large
files in an environment that requires no data redundancy. RAID 0 breaks the
data down into segments and writes each segment to a separate physical disk.
I/O performance is greatly improved by spreading the I/O load across many
physical disks. Although it offers the best performance of any RAID level,
RAID 0 lacks data redundancy. Choose this option only for non-critical data,
because failure of one physical disk results in the loss of all data. Examples of
RAID 0 applications include video editing, image editing, prepress
applications, or any application requiring high bandwidth.
RAID 1
RAID 1 uses disk mirroring so that data written to one physical disk is
simultaneously written to another physical disk. This RAID level offers fast
performance and the best data availability, but also the highest disk overhead.
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