RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that allows a system to use several hard drives as one single logical unit. To put it differently, all of the drives are used as one and the data on all of them is the same. This kind of a configuration has 2 major advantages over using a single drive to save data - the first one is redundancy, so in case one drive fails, the data will be accessed from the others, and the second one is improved performance since the input/output, or reading/writing operations will be distributed among multiple drives. You can find different RAID types in accordance with what amount of drives are used, whether reading and writing are both performed from all of the drives simultaneously, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, etc. Determined by the particular setup, the fault tolerance and the performance may vary.
RAID in Hosting
The disk drives that we employ for storage with our innovative cloud hosting platform are not the traditional HDDs, but super fast solid-state drives (SSD). They operate in RAID-Z - a special setup created for the ZFS file system which we employ. All the content that you upload to the hosting
account will be stored on multiple hard disks and at least one will be used as a parity disk. This is a special drive where an extra bit is included to any content copied on it. If a disk in the RAID fails, it'll be replaced without service interruptions and the info will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk plus that on the remaining disks. This is done in order to ensure the integrity of the info and along with the real-time checksum authentication that the ZFS file system runs on all drives, you will never need to worry about the loss of any information no matter what.
RAID in Semi-dedicated Hosting
The SSD drives which are used for storing any website content uploaded to the semi-dedicated hosting
accounts that we provide work in RAID-Z. This is a specific configuration where one or more hard drives are used for parity i.e. the system will include an extra bit to any data copied on this type of a disk drive. If a disk fails and is replaced with another one, what information will be cloned on the latter will be a combination calculated between the data on the remaining hard disks and that on the parity one. This is done to guarantee that the data on the new drive shall be accurate. Throughout the procedure, the RAID will continue functioning adequately and the faulty drive will not affect the normal operation of your Internet sites in any way. Using SSDs in RAID-Z is an impressive addition to the ZFS file system which runs on our state-of-the-art cloud platform in terms of preserving the integrity of your files as ZFS uses specific digital identifiers named checksums in order to prevent silent data corruption.