RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which allows a system to use many hard drives as a single logical unit. In other words, all of the drives are used as one and the info on all of them is the same. This kind of a configuration has two huge advantages over using just a single drive to keep data - the first one is redundancy, so if one drive breaks down, the information will be accessed through the remaining ones, and the second one is improved performance because the input/output, or reading/writing operations will be spread among multiple drives. There are different RAID types depending on what amount of drives are used, if reading and writing are both executed from all 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. According to the exact setup, the error tolerance and the performance vary.
RAID in Cloud Web Hosting
The SSD drives that 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 uses the so-called parity disk - a special drive where info saved on the other drives is cloned with an extra bit added to it. If one of the disks stops functioning, your Internet sites shall continue working from the other ones and as soon as we replace the problematic one, the info which will be copied 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 every single file correctly and to authenticate the integrity of the data cloned on the new drive. This is one more level of security for the info which you upload to your cloud web hosting
account together with the ZFS file system that analyzes a special digital fingerprint for every single file on all of the disk drives in real time.