RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that permits a system to use a number of hard drives as one single logical unit. In other words, all of the drives are used as one and the information on all of them is the same. This type of a setup has two key advantages over using a single drive to save data - the first is redundancy, so in case one drive stops working, the info will be accessed through 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 depending on what amount of drives are employed, if reading and writing are both done from all drives at the same time, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. According to the particular setup, the error tolerance and the performance could differ.
RAID in Shared Hosting
The state-of-the-art cloud web hosting platform where all shared hosting accounts are created employs quick SSD drives as opposed to the traditional HDDs, and they work in RAID-Z. With this setup, numerous hard disk drives function together and at least one of them is a dedicated parity disk. Put simply, when data is written on the rest of the drives, it is copied on the parity one adding an extra bit. This is carried out for redundancy as even if a drive fails or falls out of the RAID for some reason, the data can be rebuilt and verified using the parity disk and the data saved on the other ones, therefore not a single thing will be lost and there will be no service disorders. This is one more level of protection for your information together with the top-notch ZFS file system which uses checksums to make sure that all of the data on our servers is intact and is not silently corrupted.