www.gateway.com

Drawback

RAID 1 treats the entire array as a single drive with the storage capacity of the smallest physical drive in the array. So if you have two drives (300 GB and 250 GB) in a RAID 1 array, your computer only recognizes a single drive with 250 GB total capacity.

RAID 5 and 10 for both performance and security

Understanding RAID 5

RAID 5 uses striping (at the file level) with on-the-fly error correction across all drives. Because of this error correction, small file read/write errors can be quickly and automatically fixed without a significant drop in system performance. RAID 5 offers good performance and data redundancy. This array preserves your files if a drive fails.

RAID 5 stripes both data and parity information (error-checking information) across multiple drives. Striping across drives improves overall performance, and the parity information provides data protection. Because of the error-correction capabilities, if a drive fails, the data can be quickly and automatically fixed.

In the following graphic, each letter represents a unique block of data, and the number next to each letter represents which copy of the data files are stored on that drive. The “P” next to a letter represents parity (error-checking) information, and each column represents a separate hard drive.

RAID 5

A1A2AP

B1

BP

B2

CPC1C2

Understanding RAID 10

RAID 10 (also called RAID 1+0 or RAID 1&0) contains sets of RAID 1 mirrors acting as drives within a RAID 0 striping array. With this setup, the array could survive one drive failure in each mirrored array.

41