Redundant Array of Independent Disks, or RAID, is a method of storing content on multiple hard disk drives concurrently. A RAID could be software or hardware based on the HDDs that are used - physical or logical ones, but what’s common between them is that they all work as a single unit where your information is saved. The main advantage of using a RAID is redundancy as the info on all the drives shall be exactly the same at all times, so even in the event that one of the drives fails for some reason, the information will still be available on the remaining drives. The general performance is enhanced as well because the reading and writing processes can be split between different drives, so a single one won't be overloaded. There are different kinds of RAIDs where the effectiveness and fault tolerance may vary depending on the specific setup - whether data is written on all 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 Web Hosting
All content which you upload to your new web hosting account will be placed on quick SSD drives which work in RAID-Z. This configuration is built to work with the ZFS file system which runs on our cloud hosting platform and it adds one more level of security for your site content in addition to the real-time checksum validation which ZFS uses to ensure the integrity of the data. With RAID-Z, the information is saved on several disks and at least 1 is a parity disk - whenever information is recorded on it, an extra bit is added, so in the event that any drive stops working for whatever reason, the stability of the information can be verified by recalculating its bits in accordance with what is saved on the production hard drives and on the parity one. With RAID-Z, the functioning of our system won't be interrupted and it'll continue functioning efficiently until the problematic drive is replaced and the data is synchronized on it.