Redundant Array of Independent Disks, or RAID, is a way of keeping content on a number of hard drives at the same time. A RAID could be software or hardware based on the drives which are used - physical or logical ones, still what is common between them is the fact that they all function as just one single unit where info is stored. The top advantage of using a RAID is redundancy as the data on all the drives is exactly the same all the time, so even in case a drive fails for some reason, the information will still be present on the rest of the drives. The general performance is enhanced as well because the reading and writing processes could be split between a number of drives, so a single one will not be overloaded. There're different sorts of RAIDs where the effectiveness and fault tolerance may vary according to the particular setup - whether data is written on all the drives real-time or it's written on a single drive and after that mirrored on another, what number of drives are used for the RAID, and many others.
RAID in Shared Hosting
All of the content which you upload to your new shared hosting account will be saved on fast SSD drives which work in RAID-Z. This setup is built to use the ZFS file system which runs on our cloud web hosting platform and it adds another level of security for your website content in addition to the real-time checksum validation which ZFS uses to ensure the integrity of the data. With RAID-Z, the data is saved on a couple of disks and at least one of them is a parity disk - whenever info is written on it, an additional bit is added, so in the event that any drive fails for whatever reason, the stability of the data can be verified by recalculating its bits based on what is saved on the production disks and on the parity one. With RAID-Z, the functioning of our system will not be interrupted and it'll continue operating efficiently until the malfunctioning drive is replaced and the information is synced on it.