RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that makes it possible for a system to use many hard drives as a single logical unit. Simply put, all drives are used as one and the data on all of them is identical. This kind of a configuration has 2 major advantages over using a single drive to store data - the first one is redundancy, so in case one drive fails, the information will be accessed from the remaining ones, and the second one is better performance as the input/output, or reading/writing operations will be distributed among a number of drives. There're different RAID types depending on the number of drives are employed, whether reading and writing are both performed 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. Depending on the exact setup, the fault tolerance and the performance may vary.
RAID in Shared Web Hosting
Any content that you upload to your new shared web hosting account will be stored on quick SSD drives which function in RAID-Z. This configuration is built to employ the ZFS file system that runs on our cloud Internet hosting platform and it adds another level of security for your site content in addition to the real-time checksum authentication that ZFS uses to guarantee the integrity of the data. With RAID-Z, the data is saved on a number of disks and at least one of them is a parity disk - whenever info is recorded on it, an additional bit is added, so if any drive stops working for some reason, the stability of the data can be verified by recalculating its bits in accordance with what is stored on the production disks and on the parity one. With RAID-Z, the functioning of our system won't be interrupted and it will continue working smoothly until the faulty drive is changed and the data is synced on it.