I/O performance is greatly improved by spreading the I/O load across many physical disks. Although it offers the best performance of any RAID level, RAID 0 lacks data redundancy. Choose this option only for non-critical data, because failure of one physical disk results in the loss of all data. Examples of RAID 0 applications include video editing, image editing, prepress applications, or any application that requires high bandwidth.

RAID 1

RAID 1 uses disk mirroring so that data written to one physical disk is simultaneously written to another physical disk. RAID 1 offers fast performance and the best data availability, but also the highest disk overhead. RAID 1 is recommended for small databases or other applications that do not require large capacity. For example, accounting, payroll, or financial applications. RAID 1 provides full data redundancy.

RAID 5

RAID 5 uses parity and striping data across all physical disks (distributed parity) to provide high data throughput and data redundancy, especially for small random access. RAID 5 is a versatile RAID level and is suited for multi- user environments where typical I/O size is small and there is a high proportion of read activity such as file, application, database, web, e-mail, news, and intranet servers.

RAID 6

RAID 6 is similar to RAID 5 but provides an additional parity disk for better redundancy. RAID 6 is the most versatile RAID level and is suited for multi- user environments where typical I/O size is small and there is a high proportion of read activity. RAID 6 is recommended when large size physical disks are used or large number of physical disks are used in a disk group.

RAID 10

RAID 10, a combination of RAID 1 and RAID 0, uses disk striping across mirrored disks. It provides high data throughput and complete data redundancy. Utilizing an even number of physical disks (four or more) creates a RAID level 10 disk group and/or virtual disk. Because RAID levels 1 and 10 use disk mirroring, half of the capacity of the physical disks is utilized for mirroring. This leaves the remaining half of the physical disk capacity for

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Planning: MD3600i Series Storage Array Terms and Concepts

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Dell MD3620I, MD3600I owner manual Raid