RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard disk drives which operate together as a single logical unit. The drives can be physical or logical i.e. in the latter case one single drive is split into individual ones using virtualization software. In any case, the same information is saved on all the drives and the basic advantage of employing this type of a setup is that if a drive stops working, the data shall still be available on the other ones. Employing a RAID also improves the overall performance since the input and output operations will be spread among a few drives. There are several types of RAID dependant upon how many hard disks are used, whether writing is done on all the drives in real time or just on a single one, and how the data is synced between the hard drives - whether it is written 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 as well as the performance between the various RAID types may vary.
RAID in Cloud Web Hosting
The revolutionary cloud hosting platform where all cloud web hosting accounts are created uses fast SSD drives instead of the classic HDDs, and they work in RAID-Z. With this setup, numerous hard drives function together and at least a single one is a dedicated parity disk. Basically, when data is written on the rest of the drives, it is cloned on the parity one adding an extra bit. This is done for redundancy as even in case some drive fails or falls out of the RAID for some reason, the info can be rebuilt and verified using the parity disk and the data recorded on the other ones, thus absolutely nothing will be lost and there will be no service disturbances. This is an additional level of protection for your info along with the revolutionary ZFS file system which uses checksums to ensure that all data on our servers is intact and is not silently corrupted.