Striping Methods; Raid Levels - HP AD510A - StorageWorks Modular Smart Array 1500 cs 2U Fibre Channel SAN Attach Controller Shelf Hard Drive Installation Manual

Striping methods

A storage array combines the capacity of several physical hard drives into one
virtual unit called an array. These arrays are then presented to the operating
system as a single disk device. The physical layout of an array can be one of two
configurations:
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In a vertical configuration, an array uses hard drives from separate storage
enclosures and different SCSI buses. In a horizontal configuration, the array uses
multiple drives contained within the same storage enclosure.

RAID levels

In conjunction with the striping method, the assigned RAID level also determines
the fault-tolerance, I/O performance, and storage efficiency of the LUN.
See
When selecting a RAID level for a LUN, consider the type of data that will be
stored on the array. For example:
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Depending on the assigned RAID level, one or more drives within a LUN can fail
without bringing the drive sub-system down.
HP StorageWorks 1500 Modular Smart Array Installation Guide
Vertical striping—Offers ultimate fault tolerance and performance, but at the
price of storage efficiency.
Horizontal striping—Allows for the creation of large arrays and efficient use
of storage capacity, but at the price of I/O performance and less fault
tolerance.
Table 3 on page 32 for a comparison list of the different RAID levels.
For transitional data you may want to use RAID 0, which provides no fault
tolerance, but provides rapid storage and access of large amounts of data.
For critical data use a fault-tolerant RAID level, such as RAID 1, RAID 1+0,
RAID 5, or RAID 6. Choose the RAID level that offers the desired
combination of fault-tolerance, I/O performance, and storage efficiency.
Installation Procedures - All Deployments
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