RAID, or Redundant Array of Independent Disks, is a technology of keeping data on several hard disk drives which operate together as a single logical unit. The drives can be physical or logical i.e. in the second case a single drive is split into independent ones through virtualization software. In any case, the same info is kept on all of the drives and the basic advantage of using this type of a setup is that in the event that a drive fails, the data will still be available on the other ones. Having a RAID also boosts the performance as the input and output operations will be spread among a few drives. There are several types of RAID dependant upon how many drives are used, whether writing is carried out on all the drives in real time or just on a single one, and how the data is synchronized between the drives - whether it is recorded in blocks on one drive after another or it is mirrored from one on the others. All of these factors mean that the fault tolerance and the performance between the different RAID types may differ.

RAID in Website Hosting

The drives that we employ for storage with our state-of-the-art cloud web hosting platform are not the standard HDDs, but quick NVMes. They work in RAID-Z - a special setup developed for the ZFS file system that we work with. Any content that you upload to the website hosting account will be kept on multiple disk drives and at least one shall be employed as a parity disk. This is a special drive where an extra bit is added to any content copied on it. In case a disk in the RAID fails, it will be changed with no service interruptions and the info 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 so as to ensure the integrity of the data and together with the real-time checksum validation that the ZFS file system runs on all drives, you won't ever need to concern yourself with the loss of any info no matter what.