RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard drives which work together as one logical unit. The drives could be physical or logical i.e. in the latter case a single drive is split into different ones through virtualization software. In either case, the very same information is kept on all the drives and the main advantage of using this type of a setup is that if a drive stops working, the data will still be available on the remaining ones. Employing a RAID also boosts the performance because the input and output operations will be spread among a few drives. There are several kinds of RAID based on how many hard drives are used, whether writing is carried out on all of the drives in real time or just on a single one, and how the information is synchronized between the drives - whether it's recorded in blocks on one drive after another or it is mirrored from one on the others. These factors indicate that the fault tolerance and the performance between the various RAID types could differ.
RAID in Web Hosting
Our state-of-the-art cloud Internet hosting platform where all web hosting accounts are created employs quick SSD drives instead of the standard HDDs, and they operate in RAID-Z. With this configuration, several hard disk drives function together and at least 1 is a dedicated parity disk. In simple terms, 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 whatever reason, the information can be rebuilt and verified thanks to the parity disk and the data recorded on the other ones, so nothing will be lost and there will not be any service interruptions. This is one more level of protection for your data together with the cutting-edge ZFS file system that uses checksums to guarantee that all data on our servers is intact and is not silently corrupted.