RAID, or Redundant Array of Independent Disks, is a technology for saving data on multiple hard disk drives that operate together as one single logical unit. The drives can be physical or logical i.e. in the latter case one single drive is split into different ones through virtualization software. In either case, exactly the same info is stored on all the drives and the basic benefit of using this kind of a setup is that in case a drive fails, the data shall still be available on the remaining ones. Using a RAID also improves the performance as the input and output operations will be spread among a couple of drives. There are several kinds of RAID depending on how many hard drives are used, whether writing is performed on all drives in real time or just on a single one, and how the info is synced 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 of these factors imply that the fault tolerance and the performance between the different RAID types may vary.
RAID in Shared Website Hosting
The hard disks which we use for storage with our state-of-the-art cloud Internet hosting platform are not the standard HDDs, but quick NVMes. They function in RAID-Z - a special setup intended for the ZFS file system that we use. Any content that you upload to the shared website hosting account will be stored on multiple disk drives and at least one of them will be used as a parity disk. This is a special drive where an additional bit is included to any content copied on it. If a disk in the RAID fails, it will be changed without any service disturbances and the data will be recovered on the new drive by recalculating its bits using the data on the parity disk along with that on the other disks. This is done in order to ensure the integrity of the information and together with the real-time checksum authentication which the ZFS file system performs 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 info uploaded to any semi-dedicated server account is saved on NVMe drives that function in RAID-Z. One of the drives in type of a configuration is used for parity - every time data is copied on it, an extra bit is added. In case a disk turns out to be defective, it will be taken out of the RAID without disturbing the operation of the sites because the data will load from the rest of the drives, and when a new drive is included, the information that will be duplicated on it will be a mix between the info on the parity disk and data kept on the other hard drives in the RAID. That is done to ensure that the data that is being duplicated is accurate, so as soon as the new drive is rebuilt, it could be incorporated into the RAID as a production one. This is one more warranty for the integrity of your information as the ZFS file system that runs on our cloud Internet hosting platform analyzes a special checksum of all the copies of your files on the various drives to avoid any possibility of silent data corruption.
RAID in VPS Servers
All VPS server accounts that we offer are generated on physical servers that take advantage of NVMe drives working in RAID. At least one drive is used for parity - one extra bit is included in the information duplicated on it and in case a main disk stops working, this bit makes it much easier to recalculate the bits of the files on the failed drive so that the accurate data is restored on the new drive added to the RAID. In the mean time, your sites will still be online since all the data will still load from at least 1 other hard disk. If you add regular backups to your VPS package, a copy of the info will be kept on standard hard disks that also work in RAID because we would like to make sure that any type of content you upload will be safe and sound all of the time. Employing multiple hard drives in RAID for all the main and backup servers enables us to offer fast and reliable Internet hosting service.