RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that makes it possible for a system to take advantage of multiple hard drives as a single logical unit. Put simply, all the drives are used as one and the data on all of them is the same. This type of a configuration has two major advantages over using a single drive to save data - the first is redundancy, so in the event that one drive breaks down, the data will be accessed from the remaining ones, and the second is better performance since the input/output, or reading/writing operations will be distributed among a number of drives. There're different RAID types in accordance with how many drives are employed, if reading and writing are both handled from all of the drives simultaneously, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. According to the particular setup, the error tolerance and the performance may differ.
RAID in Cloud Hosting
The hard disks that we use for storage with our outstanding cloud Internet hosting platform are not the classic HDDs, but high-speed NVMes. They function in RAID-Z - a special setup intended for the ZFS file system that we work with. All the content that you add to your cloud hosting account will be stored on multiple hard drives and at least 1 shall be employed as a parity disk. This is a special drive where an additional bit is added to any content copied on it. If a disk in the RAID stops functioning, it'll be changed without service disturbances and the data will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk plus that on the remaining disks. This is done to ensure the integrity of the information and along with the real-time checksum validation which the ZFS file system executes on all drives, you won't ever need to concern yourself with losing any info no matter what.