RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that allows a system to use several hard drives as a single logical unit. In other words, all the drives are used as one and the info on all of them is the same. This type of a configuration has two key advantages over using a single drive to keep data - the first is redundancy, so in case one drive doesn't work, the info will be accessed through the others, and the second one is improved performance as the input/output, or reading/writing operations will be spread among multiple drives. There are different RAID types in accordance with how many drives are employed, if reading and writing are both executed from all the drives simultaneously, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. According to the exact setup, the fault tolerance and the performance could differ.
RAID in Cloud Web Hosting
Our advanced cloud hosting platform where all cloud web hosting accounts are generated uses fast SSD drives as opposed to the standard HDDs, and they function in RAID-Z. With this configuration, multiple hard drives function together and at least one of them is a dedicated parity disk. Basically, when data is written on the other drives, it is duplicated 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 thanks to the parity disk and the data recorded on the other ones, therefore practically nothing will be lost and there won't be any service disturbances. This is one more level of protection for your information in addition to the state-of-the-art ZFS file system that uses checksums to guarantee that all data on our servers is intact and is not silently corrupted.
RAID in Semi-dedicated Servers
In case you host your websites inside a semi-dedicated server account from our firm, any content you upload will be stored on SSD drives which operate in RAID-Z. With this type of RAID, at least 1 of the drives is used for parity - when data is synced between the disks, an extra bit is added to it on the parity one. The purpose behind this is to guarantee the integrity of the data that is copied to a new drive in case one of the hard drives in the RAID fails as the site content being copied on the brand new disk is recalculated from the data on the standard hard drives and on the parity one. Another advantage of RAID-Z is that even in case a hard drive stops working, the system can switch to another one quickly without service interruptions of any type. RAID-Z adds an additional level of safety for the content which you upload on our cloud web hosting platform together with the ZFS file system that uses unique checksums as a way to authenticate the integrity of each file.