Redundant Array of Independent Disks, or RAID, is a way of keeping content on multiple hard disks simultaneously. A RAID could be software or hardware based on the drives that are used - physical or logical ones, still what’s common between them is the fact that they all perform as just a single unit where information is stored. The key advantage of employing a RAID is redundancy as the information on all drives shall be identical at all times, so even in the event that one of the drives fails for whatever reason, the data will still be available on the other drives. The overall performance is also better because the reading and writing processes will be split between various drives, so a single one won't be overloaded. There are different kinds of RAIDs where the functionality and fault tolerance may vary according to the exact setup - whether information is written on all of the drives real-time or it's written on a single drive and afterwards mirrored on another, what number of drives are used for the RAID, etc.
RAID in Cloud Hosting
The hard drives that we employ for storage with our revolutionary cloud hosting platform are not the classic HDDs, but extremely fast 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 the cloud hosting account will be stored on multiple drives and at least one of them will be used as a parity disk. This is a special drive where an additional bit is added to any content copied on it. In the event that a disk in the RAID fails, it will be replaced with no service disturbances and the data will be rebuilt 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 ensure the integrity of the data and together with the real-time checksum verification which the ZFS file system executes on all drives, you will never have to worry about the loss of any info no matter what.
RAID in Semi-dedicated Hosting
The data uploaded to any semi-dedicated hosting account is stored on NVMe drives which work in RAID-Z. One of the drives in type of a setup is used for parity - every time data is cloned on it, an additional bit is added. If a disk happens to be defective, it will be removed from the RAID without interrupting the work of the sites as the data will load from the other drives, and when a new drive is included, the data which will be duplicated on it will be a combination between the information on the parity disk and data kept on the other drives in the RAID. That is done to guarantee that the information which is being cloned is correct, so as soon as the new drive is rebuilt, it can be integrated into the RAID as a production one. This is one more warranty for the integrity of your info as the ZFS file system which runs on our cloud Internet hosting platform compares a unique checksum of all the copies of the files on the separate drives to avoid any probability of silent data corruption.