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QNAP

QuTS hero 5.0.x

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RAID

Redundant array of independent disks (RAID) combines multiple physical disks into a single storage unit, and then distributes data across the disks in one of several predefined methods.

The following features make RAID ideal for use with data storage and NAS applications.

RAID Feature

Description

Advantages

Disadvantages

Grouping

Disks that are combined using RAID form a RAID group, which QuTS hero considers one large logical disk.

Managing the storage space of one large disk is simpler and more efficient than multiple small disks.

Initial configuration can be more complicated.

Striping

Data is split into smaller pieces. Each piece is stored on a different disk in the RAID group. QuTS hero can then access that data by reading from or writing to multiple disks simultaneously, increasing read and write speeds.

  • Greater read/write speeds, compared to a single disk

  • Speeds can be increased further by adding disks

If one disk in the RAID group fails, and the RAID group has no redundancy, all data will be lost.

Redundancy

Each disk in the RAID group can store the following:

  • Complete copy of the stored data

  • Metadata that allows reconstruction of lost data

  • Disks can fail or be removed from the RAID group without any loss of data

  • Users can access data while failed disks are being replaced

Total storage capacity of the RAID group is reduced.