RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard disk drives which function together as one single logical unit. The drives can be physical or logical i.e. in the latter case one single drive is divided into separate ones using virtualization software. In any case, the same data is kept on all the drives and the main benefit of employing such a setup is that in case a drive breaks down, the data will remain available on the remaining ones. Employing a RAID also boosts the overall performance since the input and output operations will be spread among several drives. There are several kinds of RAID dependant upon how many drives are used, whether writing is done on all the drives in real time or just on a single one, and how the information is synced between the drives - whether it's written in blocks on one drive after another or it is mirrored from one on the others. All of these factors mean that the fault tolerance and the performance between the various RAID types could differ.
RAID in Cloud Web Hosting
Our state-of-the-art cloud hosting platform where all cloud web hosting accounts are created uses quick NVMe drives as opposed to the traditional HDDs, and they operate in RAID-Z. With this configuration, multiple hard disk drives work together and at least a single one is a dedicated parity disk. Simply put, when data is written on the remaining drives, it's 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 using the parity disk and the data recorded on the other ones, therefore practically nothing will be lost and there will not be any service interruptions. This is one more level of security for your data together with the top-notch ZFS file system that uses checksums to ensure that all data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Servers
The information uploaded to any semi-dedicated server account is stored on NVMe drives that operate in RAID-Z. One of the drives in type of a setup is used for parity - every time data is copied on it, an extra bit is added. In case a disk happens to be problematic, it will be removed from the RAID without disturbing the operation of the websites because the data will load from the remaining drives, and when a new drive is included, the info which will be copied on it will be a mix between the data on the parity disk and data kept on the other drives in the RAID. This is done in order to guarantee that the data which is being duplicated is accurate, so the moment the new drive is rebuilt, it could be included in the RAID as a production one. This is one more guarantee for the integrity of your data as the ZFS file system that runs on our cloud web hosting platform analyzes a unique checksum of all copies of the files on the separate drives to avoid any possibility of silent data corruption.
RAID in VPS Servers
The NVMe drives that we use on the physical machines where we generate VPS servers operate in RAID to ensure that any content that you upload will be available and intact all the time. At least a single drive is used for parity - one bit of info is added to any data cloned on it. In the event that a main drive stops working, it is changed and the data which will be copied on it is calculated between the other drives and the parity one. That’s done to make sure that the correct data is copied and that no file is corrupted as the new drive will be used in the RAID afterwards. In addition, we use hard disks operating in RAID on the backup servers, so in the event that you add this upgrade to your VPS package, you will use an even more reliable hosting service as your content will be available on multiple drives regardless of any unforeseen hardware malfunction.