Western Digital Storage Solutions

RAID – or Redundant Array of Independent Disks – is a type of storage that writes data across multiple drives within the same system. Different configurations are expressed as numbers, such as RAID 0, RAID 1, or RAID 5. Each RAID type gives users different benefits — increased performance, greater fault tolerance, or a combination of both — depending on how it writes and distributes your data.

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RAID 0 offers the fastest read/write speeds and maximum availability of raw storage capacity. Although RAID is typically associated with data redundancy, RAID 0 does not provide any. However, it does provide the best performance of any RAID level.

It achieves this by breaking up data into smaller groups and storing it on separate disks. For example, in a two-disk array, the data is split evenly across the two disks, doubling your speed. In a four-disk array, you can quadruple your speed, and so on.

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RAID 1 is an excellent option when data protection and redundancy is your primary goal. This RAID type stores your data on one disk and then keeps a separate copy of that data on each of the available remaining disks.

This means that if one disk goes down, you still have your data ready to go. This approach gives you the usable storage capacity and write speeds of one disk but offers strong data protection.

Requiring a RAID system of three or more drives, RAID 5 offers the best of both worlds, balancing performance and redundancy.

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It does this by splitting data into groups across all available drives and creating distributed parity, where data calculations are stored across the drives so that any one drive may fail, and the data — or parity — on the other drives can reconstitute what was lost on the failed drive.

This is a faster setup than a RAID 1but allows for single-disk fault tolerance (no matter how many are in the array) unlike RAID 0, providing both speed and data protection.

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RAID 10 nests at least two RAID 1 sets within a RAID 0 configuration. This blends performance with potentially higher fault tolerance. Mirroring lends additional redundancy, which means that you can retain your data even if you lose up to half your disks — provided your mirrored copy does not fail.

This is why businesses and other professional teams use RAID 10 where uptime and availability are critical for intense workflows.

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JBOD and JBOF, or Just a Bunch of Disks and Just a Bunch of Flash, respectively, open up additional paths to flexibility with a RAID storage device.

While arrays using numbered RAID types generally require reformatting to add new drives, JBOD and JBOF allow users to expand or swap drives without reformatting.

JBOD can do this because each disk acts independently, and each disk is seen as its own volume. This also means the risk of data loss is contained to one drive rather than the entire array.

With Spanning, data is only kept within each disk, but the system make all disks appear as one larger "logical" volume — almost like they're one big drive. Spanning is more flexible than RAID and simpler to use than JBOD, but it can be more complex than JBOD if you want to move drives.