RAID, or Redundant Array of Independent Disks, is a technology of storing data on multiple hard disk drives which operate together as one logical unit. The drives can be physical or logical i.e. in the second case a single drive is divided into separate ones through virtualization software. Either way, exactly the same info is kept on all of the drives and the key benefit of employing such a setup is that in the event that a drive breaks down, the data shall still be available on the other ones. Employing a RAID also boosts the overall performance because the input and output operations will be spread among a couple of drives. There are several kinds of RAID dependant upon how many drives are used, whether writing is done on all the drives in real time or just on one, and how the info is synced between the drives - whether it is written in blocks on one drive after another or it is mirrored from one on the others. All these factors mean that the error tolerance and the performance between the different RAID types could differ.
RAID in Hosting
Our revolutionary cloud web hosting platform where all hosting accounts are made employs fast SSD drives as opposed to the standard HDDs, and they operate in RAID-Z. With this configuration, multiple hard disks function together and at least one is a dedicated parity disk. Simply put, when data is written on the other drives, it is duplicated on the parity one adding an extra bit. This is done for redundancy as even if some drive fails or falls out of the RAID for some reason, the information can be rebuilt and verified thanks to the parity disk and the data saved on the other ones, therefore not a single thing will be lost and there will not be any service interruptions. This is one more level of security for your data along with the revolutionary ZFS file system that uses checksums to guarantee that all the data on our servers is intact and is not silently corrupted.