RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that allows a system to use several hard drives as a single logical unit. To put it differently, all drives are used as one and the information 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 one is redundancy, so if one drive fails, the information will be accessed through the others, and the second is better performance since the input/output, or reading/writing operations will be distributed among a number of drives. You can find different RAID types depending on the number of drives are employed, 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, etcetera. Based on the exact setup, the error tolerance and the performance could differ.
RAID in Cloud Website Hosting
The cutting-edge cloud web hosting platform where all cloud website hosting accounts are generated employs fast SSD drives as an alternative to the traditional HDDs, and they work in RAID-Z. With this configuration, multiple hard drives function together and at least one of them is a dedicated parity disk. Simply put, when data is written on the remaining drives, it is duplicated on the parity one adding an extra bit. This is carried out for redundancy as even in case a drive fails or falls out of the RAID for whatever reason, the data can be rebuilt and verified thanks to the parity disk and the data recorded on the other ones, therefore not a single thing will be lost and there won't be any service disturbances. This is one more level of security for your data in addition to the top-notch ZFS file system which uses checksums to guarantee that all the data on our servers is intact and is not silently corrupted.