RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that makes it possible for a system to employ many hard drives as a single logical unit. To put it differently, all of the drives are used as one and the information on all of them is identical. Such a configuration has 2 huge advantages over using just a single drive to store data - the first is redundancy, so in the event that one drive breaks down, the information will be accessed through the remaining ones, and the second one is better performance because the input/output, or reading/writing operations will be spread among a number of drives. There're different RAID types in accordance with how many drives are used, if reading and writing are both handled from all drives concurrently, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, etcetera. Depending on the particular setup, the fault tolerance and the performance could differ.
RAID in Shared Hosting
Our advanced cloud hosting platform where all shared hosting
accounts are generated uses super fast SSD drives as opposed to the traditional HDDs, and they operate in RAID-Z. With this configuration, a number of hard disks work together and at least one is a dedicated parity disk. In simple terms, when data is written on the rest of the drives, it's cloned on the parity one adding an extra bit. This is performed for redundancy as even in case some drive fails or falls out of the RAID for whatever reason, the information can be rebuilt and verified thanks to the parity disk and the data saved on the other ones, thus absolutely nothing will be lost and there won't be any service disorders. This is an additional level of security for your information along with the advanced ZFS file system which uses checksums to guarantee that all the data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Hosting
In case you host your sites in a semi-dedicated hosting
account from our company, all of the content which you upload will be saved on SSD drives which work in RAID-Z. With this kind of RAID, at least one of the hard drives is used for parity - when data is synced between the drives, an additional bit is added to it on the parity one. The purpose behind this is to ensure the integrity of the data that is copied to a new drive in case one of the hard drives in the RAID breaks down as the site content being copied on the new disk is recalculated from the information on the standard drives and on the parity one. An additional advantage of RAID-Z is that even if a disk drive fails, the system can easily switch to another one immediately without service disturbances of any kind. RAID-Z adds an additional level of security for the content which you upload on our cloud web hosting platform in addition to the ZFS file system which uses unique checksums as a way to validate the integrity of each file.