RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that enables a system to take advantage of multiple hard drives as a single logical unit. Put simply, all the drives are used as one and the info on all of them is the same. This kind of a setup has two major advantages over using a single drive to store data - the first is redundancy, so in the event that one drive doesn't work, the info will be accessible through the remaining ones, and the second is better performance because the input/output, or reading/writing operations will be distributed among several drives. You can find different RAID types in accordance with how many drives are used, whether reading and writing are both executed from all the drives simultaneously, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. Depending on the exact setup, the error tolerance and the performance vary.
RAID in Shared Web Hosting
The revolutionary cloud Internet hosting platform where all shared web hosting accounts are made uses fast SSD drives as opposed to the classic HDDs, and they operate in RAID-Z. With this setup, multiple hard disk drives operate together and at least a single one is a dedicated parity disk. In simple terms, when data is written on the rest of the drives, it's copied on the parity one adding an extra bit. This is performed for redundancy as even in case some drive fails or falls out of the RAID for some reason, the info can be rebuilt and verified thanks to the parity disk and the data saved on the other ones, thus nothing will be lost and there won't be any service disorders. This is one more level of security for your information together with the state-of-the-art ZFS file system that uses checksums to ensure that all of the data on our servers is intact and is not silently corrupted.