Redundant Array of Independent Disks, or RAID, is a method of storing content on a number of hard disk drives simultaneously. A RAID can be software or hardware depending on the hard drives which are used - physical or logical ones, but what is common between them is the fact that they all work as just a single unit where your information is kept. The biggest advantage of employing a RAID is redundancy as the info on all drives is exactly the same all the time, so even in the event that a drive fails for some reason, the info will still be present on the remaining drives. The overall performance is also better because the reading and writing processes can be split between a number of drives, so a single one will not be overloaded. There're different types of RAIDs where the performance and fault tolerance could differ based on the specific setup - whether data is written on all of the drives in real time or it's written on one drive and afterwards mirrored on another, what amount of drives are used for the RAID, etc.
RAID in Cloud Hosting
The SSD drives that our cutting-edge cloud web hosting platform employs for storage operate in RAID-Z. This sort of RAID is created to work with the ZFS file system that runs on the platform and it works by using the so-called parity disk - a specific drive where information stored on the other drives is copied with an additional bit added to it. In the event that one of the disks stops functioning, your websites shall continue working from the other ones and after we replace the bad one, the information which will be copied on it will be recovered from what is stored on the other drives together with the info from the parity disk. This is done so as to be able to recalculate the elements of each file properly and to confirm the integrity of the information cloned on the new drive. This is one more level of security for the information that you upload to your cloud hosting account in addition to the ZFS file system that compares a special digital fingerprint for each and every file on all of the hard drives in real time.