About creating a raid set – Apple Mac OS X Server (Version 10.6 Snow Leopard) User Manual
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Additional information about diskutil and other uses can be found in Introduction to
Command-Line Administration. For complete command syntax for
diskutil,
consult
the tool’s man page.
The specific command issued depends on your disk format needs and the hardware in
use. Take care to use command-line arguments that apply to your specific needs.
The following command is a sample, which partitions a computer’s only 120 GB hard
disk into two equal 60 GB journaled HFS+ volumes (“BootDisk” and “DataStore”), which
can start up an Intel-based Mac computer.
The basic syntax is:
diskutil partitionDisk device numberOfPartitions GPTFormat part1Name part1Size> So the command is: diskutil partitionDisk disk0 2 GPTFormat JournaledHFS+ BootDisk 50% JournaledHFS+ DataStore 50% About Creating a RAID Set If you’re installing Mac OS X Server on a computer with multiple internal hard disks, For example, a mirrored RAID set increases reliability by writing your data to two or You can use Disk Utility to set up a RAID set. There are two types of RAID sets and one  A striped RAID set (RAID 0) splits files across the disks in the set. A striped RAID  A mirrored RAID set (RAID 1) duplicates files across the disks in the set. Because  A concatenated disk set lets you use several disks as a single volume. This is not a 96 Chapter 5 Installation and Deployment
you can create a RAID set to optimize storage capacity, improve performance, and
increase reliability in case of a disk failure.
more disks at once. If one disk fails, your server uses another disk in the RAID set.
additional disk option available in Disk Utility:
set improves the performance of your software because it can read and write on
all disks in the set at the same time. You might use a striped RAID set if you are
working with large files, such as digital video.
this scheme maintains copies of the files, it provides a continuous backup of them.
In addition, it can help keep data available if a disk in the set fails. Mirroring is
recommended if shared files or applications must be accessed frequently.
You can set up RAID mirroring after installing Mac OS X Server if you install on a disk
that isn’t partitioned. To prevent data loss, set up RAID mirroring as soon as possible.
true RAID set and offers no redundancy or performance increase.