RAID, or Redundant Array of Independent Disks, is a technology of keeping data on a number hard disks which function together as a single logical unit. The drives could be physical or logical i.e. in the second case one single drive is split into separate ones through virtualization software. In any case, identical data is saved on all of the drives and the key benefit of employing such a setup is that in case a drive stops working, the data will still be available on the remaining ones. Having a RAID also improves the overall performance since the input and output operations will be spread among a couple of drives. There are several types 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 data is synchronized between the drives - whether it is recorded in blocks on one drive after another or it is mirrored from one on the others. These factors show that the error tolerance and the performance between the various RAID types can differ.
RAID in Shared Hosting
The advanced cloud Internet hosting platform where all shared hosting
accounts are created employs quick SSD drives as opposed to the standard HDDs, and they function in RAID-Z. With this setup, several hard drives function together and at least one is a dedicated parity disk. Put simply, when data is written on the remaining drives, it is duplicated on the parity one adding an extra bit. This is performed for redundancy as even in case some drive fails or falls out of the RAID for some reason, the data can be rebuilt and verified thanks to the parity disk and the data stored on the other ones, so not a single thing will be lost and there will be no service disorders. This is one more level of security for your data along with the top-notch ZFS file system which uses checksums to ensure that all the data on our servers is intact and is not silently corrupted.
RAID in Semi-dedicated Servers
The RAID type which we use for the cloud web hosting platform where your semi-dedicated server
account will be created is called RAID-Z. What is different about it is that at least one of the disks is employed as a parity drive. In simple terms, whenever any kind of data is duplicated on this specific drive, one more bit is included to it and in case a faulty disk is changed, the information that will be cloned on it is a combination of the data on the remaining hard drives in the RAID and that on the parity one. We do this to guarantee that the data is intact. Throughout this process, your sites will be functioning normally since RAID-Z enables a whole drive to fail without service interruptions and it simply works by using one of the remaining ones as the main production drive. Employing RAID-Z together with the ZFS file system which uses checksums to warrant that no data will get silently corrupted on our servers, you will not have to worry about the integrity of your files.