Redundant Array of Independent Disks, or RAID, is a method of keeping content on several hard disks at the same time. A RAID could be software or hardware depending on the hard drives that are used - physical or logical ones, but what is common between them is the fact that they all perform as a single unit where information is stored. The top advantage of employing a RAID is redundancy since the data on all of the drives will be identical all the time, so even if a drive fails for whatever reason, the info will still be available on the remaining drives. The general performance is also enhanced as the reading and writing processes could be split between multiple drives, so a single one will not be overloaded. There're different kinds of RAIDs where the capabilities and fault tolerance may differ based on the specific setup - whether data is written on all the drives in real time or it is written on a single drive and afterwards mirrored on another, what number of drives are used for the RAID, and many others.
RAID in Cloud Hosting
Our state-of-the-art cloud Internet hosting platform where all cloud hosting accounts are made uses fast SSD drives instead of the traditional HDDs, and they operate in RAID-Z. With this setup, multiple hard drives function together and at least one is a dedicated parity disk. In simple terms, when data is written on the other drives, it's copied on the parity one adding an extra bit. This is carried out for redundancy as even if some drive fails or falls out of the RAID for some reason, the info can be rebuilt and verified using the parity disk and the data saved on the other ones, which means that nothing will be lost and there won't be any service disturbances. This is one more level of protection for your info along with the revolutionary ZFS file system that uses checksums to ensure that all of the data on our servers is undamaged and is not silently corrupted.