RAID, or Redundant Array of Independent Disks, is a technology of saving data on multiple hard drives that operate together as a single logical unit. The drives could be physical or logical i.e. in the aforementioned case a single drive is divided into separate ones via virtualization software. In any case, exactly the same info is saved on all the drives and the key benefit of using this kind of a setup is that if a drive stops working, the data will remain available on the other ones. Employing a RAID also improves the performance as the input and output operations will be spread among a few drives. There are several types of RAID based on how many hard drives are used, whether writing is carried out on all of the drives in real time or just on a single one, and how the data is synchronized between the hard 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 indicate that the error tolerance and the performance between the different RAID types can vary.
RAID in Cloud Hosting
The SSD drives which our cutting-edge cloud web hosting platform uses for storage operate in RAID-Z. This sort of RAID is developed to work with the ZFS file system that runs on the platform and it works by using the so-called parity disk - a specific drive where information stored on the other drives is cloned with an additional bit added to it. In case one of the disks stops working, your Internet sites will continue working from the other ones and as soon as we replace the malfunctioning one, the info which will be duplicated on it will be recovered from what is stored on the rest of the drives along with the data from the parity disk. This is done so as to be able to recalculate the bits of every file correctly and to confirm the integrity of the data duplicated on the new drive. This is one more level of security for the information that you upload to your cloud hosting account together with the ZFS file system that compares a unique digital fingerprint for each file on all disk drives in real time.