Spring Switzerland GmbH Ver. 1.61 manual RAID types

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•Lower costs by centralizing storage management.

•iSCSI also simplifies the installation and on-going management of a SAN versus using Fibre Channel.

With Open-E iSCSI, you can add storage to your existing network quickly, easily, and most important cost-efficiently. Expensive hardware is no longer necessary. Take any computer, a new rack server or an old desktop PC and exchange the system drive for the Open-E iSCSI flash module. To store data Open-E iSCSI ENTERPRISE uses IDE (ATA), SATA or SCSI hard drives and hardware RAID controllers.

Within a few minutes, you will have up to several hundred gigabytes available on your network without much effort or any downtime.

2.4 RAID types

This manual is not intended to replace your RAID controller manual. But we want to provide you with an overview of common RAID types so that you can make an informed decision on which type to choose. Depending on whom you ask, RAID means either Redundant Array of Independent Disks or Redundant Array of Inexpensive Disks. Both are correct. In essence, you combine the capacity, speed and security of several disks into one.

RAID 0 forms one large hard disk by concatenating stripes from each member drive. Stripe size is configurable roughly between 64 KB and 1 MB. The result is a lightning- fast RAID, but with no added security. One failing drive may ruin the entire RAID.

RAID 1 mirrors hard drives. By writing identical data onto more than one drive, security is enhanced. A completely defective drive does not cause any loss of data. The drawback is reduced performance and capacity.

RAID 5 combines data striping from RAID 0 with parity checking, therefore combining speed and improved security. The loss of one drive is tolerable.

RAID 6 extends RAID 5 by adding an additional parity block, thus it uses block-level striping with two parity blocks distributed across all member disks. It was not one of the original RAID levels. The user capacity of a RAID 6 array is N-2, where N is the total number of drives in the array. RAID 6 does not have a performance penalty for read operations, but it does have a performance penalty on write operations due to the overhead associated with the additional parity calculations.

RAID 10 is a combination of RAID 1 and 0, hence the name. Data is written in a striped and mirrored configuration, providing high performance and robust security.