RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that permits a system to employ 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 identical. This type of a configuration has two huge advantages over using a single drive to store data - the first one is redundancy, so in the event that one drive stops working, the info will be accessed from the others, and the second is better performance as the input/output, or reading/writing operations will be spread among multiple drives. There're different RAID types based on what amount of drives are used, if reading and writing are both done from all the drives concurrently, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and many others. Based on the exact setup, the error tolerance and the performance could differ.
RAID in Shared Hosting
Our advanced cloud hosting platform where all shared hosting accounts are made employs super fast SSD drives rather than the classic HDDs, and they work in RAID-Z. With this configuration, numerous hard drives function together and at least a single one is a dedicated parity disk. Put simply, when data is written on the rest of the drives, it is cloned 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 info can be rebuilt and verified thanks to the parity disk and the data saved on the other ones, therefore absolutely nothing will be lost and there will not be any service interruptions. This is an additional level of protection for your info in addition to the top-notch ZFS file system that uses checksums to ensure that all data on our servers is intact and is not silently corrupted.
RAID in Semi-dedicated Servers
The SSD drives that are used for saving any site content uploaded to the semi-dedicated server accounts which we offer function in RAID-Z. This is a specific configuration where one or more drives are used for parity i.e. the system will add an additional bit to any data copied on this type of a hard drive. If a disk fails and is replaced with another one, what information will be copied on the latter will be a mix calculated between the data on the other disks and that on the parity one. This is done to guarantee that the information on the new drive shall be accurate. Throughout the procedure, the RAID will continue operating normally and the faulty drive won't have an impact on the normal operation of your websites at all. Using SSDs in RAID-Z is an outstanding addition to the ZFS file system which runs on our advanced cloud platform in terms of preserving the integrity of your files because ZFS uses specific digital identifiers known as checksums in order to avoid silent data corruption.
RAID in VPS Servers
The SSD drives that we use on the physical machines where we generate VPS servers operate in RAID to ensure that any content you upload will be available and intact at all times. At least a single drive is used for parity - one bit of data is added to any data copied on it. In the event that a main drive stops working, it is changed and the information that will be copied on it is calculated between the other drives and the parity one. This is done to make sure that the required info is copied and that no file is corrupted as the new drive will be included in the RAID afterwards. In addition, we use hard disk drives working in RAID on the backup servers, so in the event that you add this upgrade to your VPS plan, you will use an even more reliable Internet hosting service since your content will be available on multiple drives regardless of any sort of unpredicted hardware failure.