RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which permits a system to use a number of hard drives as one single logical unit. Put simply, all of the drives are used as one and the info on all of them is the same. This kind of a setup has 2 huge advantages over using a single drive to store data - the first is redundancy, so in the event that one drive doesn't work, the data will be accessed from the others, and the second is improved performance because the input/output, or reading/writing operations will be spread among several drives. There are different RAID types in accordance with what number of drives are employed, if reading and writing are both done from all of the drives simultaneously, whether 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 advanced cloud hosting platform where all cloud web hosting accounts are generated uses super fast SSD drives rather than the classic HDDs, and they work in RAID-Z. With this configuration, multiple hard disks function 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 cloned on the parity one adding an extra bit. This is performed for redundancy as even in case a drive fails or falls out of the RAID for some reason, the information can be rebuilt and verified using the parity disk and the data recorded on the other ones, which means that practically nothing will be lost and there will not be any service disorders. This is one more level of security for your info together with the state-of-the-art ZFS file system which uses checksums to make sure that all the data on our servers is intact and is not silently corrupted.