RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard disk drives that function together as one logical unit. The drives can be physical or logical i.e. in the latter case one single drive is split into separate ones using virtualization software. Either way, the same data is saved on all of the drives and the key advantage of using this type of a setup is that if a drive breaks down, the data shall still be available on the other ones. Using a RAID also improves the overall performance because the input and output operations will be spread among several drives. There are several types of RAID based on how many hard drives are used, whether writing is performed on all the drives in real time or just on a single one, and how the info is synchronized between the hard drives - whether it's recorded in blocks on one drive after another or it is mirrored from one on the others. All these factors suggest that the fault tolerance and the performance between the various RAID types can vary.
RAID in Hosting
The disk drives that we use for storage with our outstanding cloud Internet hosting platform are not the classic HDDs, but high-speed NVMes. They work in RAID-Z - a special setup created for the ZFS file system which we work with. Any content that you upload to your hosting account will be kept on multiple hard drives and at least 1 shall be employed as a parity disk. This is a special drive where an additional bit is included to any content copied on it. In the event that a disk in the RAID stops working, it'll be changed without service disruptions and the data will be recovered on the new drive by recalculating its bits using the data on the parity disk plus that on the remaining disks. This is done so as to guarantee the integrity of the info and together with the real-time checksum validation that the ZFS file system executes on all drives, you will never have to be concerned about the loss of any information no matter what.
RAID in Semi-dedicated Servers
The NVMe drives that are used for storing any content uploaded to the semi-dedicated server accounts which we provide function in RAID-Z. This is a specific configuration where one or more disk drives are used for parity i.e. the system will add an extra bit to any data cloned on this kind of a drive. If a disk fails and is replaced with another one, what info will be cloned on the latter shall be a combination calculated between the data on the other drives and that on the parity one. This is done to guarantee that the data on the new drive will be accurate. During the process, the RAID will continue operating normally and the malfunctioning drive will not affect the normal operation of your Internet sites at all. Using NVMes in RAID-Z is an outstanding addition to the ZFS file system that runs on our state-of-the-art cloud platform with regard to preserving the integrity of your files as ZFS uses special digital identifiers referred to as checksums in order to avoid silent data corruption.
RAID in VPS Servers
The NVMe drives that we use on the physical machines where we generate VPS servers function in RAID to make sure that any content you upload will be available and intact all of the time. At least 1 drive is employed for parity - one bit of info is added to any data cloned on it. In the event that a main drive breaks down, it is changed and the data which will be cloned on it is calculated between the rest of the drives and the parity one. It's done this way to make sure that the required data is copied and that no file is corrupted because the new drive will be a part of the RAID afterwards. Also, we use hard drives functioning in RAID on the backup servers, so in case you add this upgrade to your VPS plan, you shall use an even more reliable hosting service as your content will be available on multiple drives regardless of any type of unpredicted hardware failure.