Redundant Array of Independent Disks, or RAID, is a way of saving content on a number of hard disk drives concurrently. A RAID can be software or hardware depending on the drives which are used - physical or logical ones, still what is common between them is that they all function as one single unit where your information is stored. The biggest advantage of employing a RAID is redundancy because the info on all the drives will be the same all the time, so even if a drive fails for whatever reason, the info will still be present on the rest of the drives. The overall performance is enhanced as well because the reading and writing processes will be split between multiple drives, so a single one won't be overloaded. There're different kinds of RAIDs where the functionality and fault tolerance could differ depending on the specific setup - whether information is written on all the drives in real time or it is written on a single drive and after that mirrored on another, the number of drives are used for the RAID, and many others.
RAID in Cloud Website Hosting
The hard disks that we use for storage with our ground-breaking cloud Internet hosting platform are not the classic HDDs, but extremely fast solid-state drives (SSD). They operate in RAID-Z - a special setup developed for the ZFS file system which we work with. Any content that you upload to the cloud website hosting account will be stored on multiple disk drives and at least one shall be used as a parity disk. This is a special drive where an additional bit is included to any content copied on it. In the event that a disk in the RAID stops functioning, it will be replaced without any service disturbances and the data will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk along with that on the remaining disks. This is done to guarantee the integrity of the information and together with the real-time checksum verification which the ZFS file system runs on all drives, you will never need to worry about losing any data no matter what.