RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which enables a system to take advantage of several hard drives as one single logical unit. Simply put, all of the drives are used as one and the information on all of them is the same. This kind of a configuration has two key advantages over using just a single drive to save data - the first one is redundancy, so in the event that one drive doesn't work, the information will be accessible through the remaining ones, and the second is improved performance because the input/output, or reading/writing operations will be spread among different drives. There're different RAID types in accordance with what amount of drives are employed, if reading and writing are both executed from all drives at the same time, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. Based on the particular setup, the error tolerance and the performance may vary.
RAID in Web Hosting
All of the content which you upload to your new web hosting account will be saved on quick SSD drives that work in RAID-Z. This setup is built to work with the ZFS file system which runs on our cloud hosting platform and it adds an additional level of security for your site content on top of the real-time checksum authentication which ZFS uses to guarantee the integrity of the data. With RAID-Z, the data is stored on a number of disks and at least 1 is a parity disk - whenever information is written on it, an additional bit is added, so in the event that any drive stops working for some reason, the integrity of the information can be verified by recalculating its bits based on what is kept on the production hard drives and on the parity one. With RAID-Z, the functioning of our system will not be interrupted and it'll continue functioning flawlessly until the faulty drive is replaced and the information is synced on it.