RAID, or Redundant Array of Independent Disks, is a technology for keeping data on multiple hard drives that operate together as one logical unit. The drives can be physical or logical i.e. in the aforementioned case a single drive is split into independent ones through virtualization software. In any case, identical data is saved on all of the drives and the basic benefit of employing such a setup is that if a drive stops working, the data shall still be available on the remaining ones. Using a RAID also enhances the overall performance because the input and output operations will be spread among a couple of drives. There are several kinds of RAID depending on how many hard drives are used, whether writing is carried out on all drives in real time or just on one, and how the information is synchronized between the drives - whether it is written in blocks on one drive after another or all of it is mirrored from one on the others. These factors indicate that the fault tolerance as well as the performance between the different RAID types may differ.
RAID in Cloud Hosting
Our advanced cloud web hosting platform where all cloud hosting accounts are created employs fast SSD drives instead of the traditional HDDs, and they function in RAID-Z. With this setup, multiple hard disks operate together and at least one is a dedicated parity disk. In simple terms, when data is written on the other drives, it's copied on the parity one adding an extra bit. This is carried out 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, 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 together with the revolutionary ZFS file system that uses checksums to guarantee that all the data on our servers is undamaged and is not silently corrupted.