Dell PowerVault MD3600i El manual del propietario descargar pdf (Pagina 41)

Planning: MD3600i Series Storage Array Terms and Concepts 41

RAID Levels

RAID levels determine the way in which data is written to physical disks.

Different RAID levels provide different levels of accessibility, redundancy, and

capacity.

Using multiple physical disks has the following advantages over using a single

physical disk:

• Placing data on multiple physical disks (striping) allows input/output (I/O)

operations to occur simultaneously and improve performance.

• Storing redundant data on multiple physical disks using mirroring or parity

supports reconstruction of lost data if an error occurs, even if that error is

the failure of a physical disk.

Each RAID level provides different performance and protection. You must

select a RAID level based on the type of application, access, fault tolerance,

and data you are storing.

The storage array supports RAID levels 0, 1, 5, 6, and 10. The maximum

number of physical disks that can be used in a disk group depends on the

RAID level:

• 192 for RAID

levels

0, 1, and 10

•30 for RAID

levels

5 and 6.

RAID Level Usage

To ensure best performance, you must select an optimal RAID level when you

create a system physical disk. The optimal RAID level for your disk array

depends on:

• Number of physical disks in the disk array

• Capacity of the physical disks in the disk array

• Need for redundant access to the data (fault tolerance)

• Disk performance requirements

RAID 0

RAID 0 uses disk striping to provide high data throughput, especially for large

files in an environment that requires no data redundancy. RAID 0 breaks the

data down into segments and writes each segment to a separate physical disk.

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Dell PowerVault MD3600i El manual del propietario Pagina 41