RAID, which stands 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 many hard drives as a single logical unit. To put it differently, all the drives are used as one and the data on all of them is the same. This type of a configuration has two huge advantages over using a single drive to save data - the first is redundancy, so if one drive stops working, the information will be accessed through the others, and the second one is improved performance because the input/output, or reading/writing operations will be spread among a number of drives. There are different RAID types in accordance with how many drives are used, whether reading and writing are both done from all of the drives at the same time, if data is written in blocks on one drive after another or is mirrored between drives in the same time, etc. Determined by the exact setup, the fault tolerance and the performance may differ.
RAID in Cloud Hosting
The SSD drives which our cutting-edge cloud hosting platform employs for storage operate in RAID-Z. This sort of RAID is designed to work with the ZFS file system which runs on the platform and it works by using the so-called parity disk - a specific drive where info stored on the other drives is duplicated with an extra bit added to it. If one of the disks fails, your websites will continue working from the other ones and once we replace the bad one, the information which will be duplicated on it will be rebuilt from what is stored on the remaining drives together with the data from the parity disk. This is done in order to be able to recalculate the elements of each file properly and to verify the integrity of the data cloned on the new drive. This is one more level of security for the content you upload to your cloud hosting account in addition to the ZFS file system which compares a special digital fingerprint for every single file on all of the drives in real time.