Redundant Array of Independent Disks, or RAID, is a way of storing content on several hard disks simultaneously. A RAID could be software or hardware depending on the HDDs that are used - physical or logical ones, still what is common between them is that they all perform as just one single unit where your information is saved. The biggest advantage of using a RAID is redundancy because the information on all drives is identical all the time, so even in the event that a drive fails for whatever reason, the data will still be present on the other drives. The overall performance is also better since the reading and writing processes can be split between different drives, so a single one can't be overloaded. There are different kinds of RAIDs where the efficiency and fault tolerance can vary based on the specific setup - whether info is written on all of the drives real-time or it's written on one drive and then mirrored on another, the number of drives are used for the RAID, and so on.
RAID in Website Hosting
The NVMe drives that our cutting-edge cloud Internet hosting platform employs for storage operate in RAID-Z. This kind of RAID is designed to work with the ZFS file system that runs on the platform and it uses the so-called parity disk - a special drive where information located on the other drives is cloned with an extra bit added to it. In case one of the disks stops functioning, your sites shall continue working from the other ones and as soon as we replace the problematic one, the information which will be copied on it will be rebuilt from what is stored on the other drives together with the data from the parity disk. This is done in order to be able to recalculate the elements of each and every file properly and to confirm the integrity of the info duplicated on the new drive. This is another level of security for the info that you upload to your website hosting account together with the ZFS file system which analyzes a unique digital fingerprint for each and every file on all the disk drives in real time.