RAID, or Redundant Array of Independent Disks, is a technology of saving data on a number hard drives which work together as a single logical unit. The drives can be physical or logical i.e. in the latter case one drive is divided into different ones using virtualization software. Either way, exactly the same information is kept on all drives and the main advantage of employing such a setup is that in the event that a drive breaks down, the data shall still be available on the remaining ones. Employing a RAID also improves the overall performance since the input and output operations will be spread among several drives. There are several types of RAID depending on how many drives are used, whether writing is done on all drives in real time or just on one, and how the information is synchronized between the hard drives - whether it is written in blocks on one drive after another or all of it is mirrored from one on the others. These factors indicate that the error tolerance as well as the performance between the various RAID types could differ.
RAID in Cloud Web Hosting
The SSD drives that our cutting-edge cloud web hosting platform employs for storage operate in RAID-Z. This type of RAID is created to work with the ZFS file system that runs on the platform and it uses the so-called parity disk - a special drive where information saved on the other drives is copied with an additional bit added to it. In the event that one of the disks fails, your websites shall continue working from the other ones and once we replace the problematic one, the information that will be cloned on it will be recovered from what is stored on the remaining drives as well as the data from the parity disk. This is done so as to be able to recalculate the bits of each and every file adequately and to verify the integrity of the data copied on the new drive. This is an additional level of security for the content which you upload to your cloud web hosting account along with the ZFS file system that compares a special digital fingerprint for every single file on all hard drives in real time.