Toshiba Magnia 560S - Manual (Page 71)

Configuring SCSI Physical Drives
Configuring RAID Controller Kit-G
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Table 5.5 Fault Tolerance for RAID Levels (Continued)
RAID Level Fault Tolerance Protection
5 100% protection through striping and parity. The data is striped and
parity data is written across a number of physical disk drives.
10 100% protection through data mirroring.
50 100% protection through data striping and parity. All data is striped
and parity data is written across all drives in two or more arrays.
Maximizing Drive Performance
You can configure an array for optimal performance; however, optimal drive
configuration for one type of application will probably not be optimal for any other
application. A basic guideline of the performance characteristics for RAID drive arrays
at each RAID level is shown in Table 5.6.
Table 5.6 Performance Characteristics for RAID Levels
RAID Level Performance Characteristics
0 Excellent for all types of I/O activity, but provides no data security.
1 Provides data redundancy and good performance.
5 Provides data redundancy and good performance in most
environments.
10 Provides data redundancy and excellent performance.
50 Provides data redundancy and very good performance.
Assigning RAID Levels
Only one RAID level can be assigned to each logical drive. Table 5.7 lists the drives
required per RAID level.
Table 5.7 Number of Physical Drives for RAID Levels
RAID Level Minimum Number of Physical
Drives Maximum Number of Physical
Drives
0 1 15
1 2 2
5 3 15
10 4 14
50 6 15
NOTE: The maximum number of physical drives supported by the
controller is 15.