RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that allows a system to take advantage of multiple hard drives as a single logical unit. In other words, all drives are used as one and the info on all of them is the same. This kind of a configuration has 2 key advantages over using a single drive to save data - the first one is redundancy, so in the event that one drive breaks down, the info will be accessible through the others, and the second is improved performance since the input/output, or reading/writing operations will be distributed among several drives. You can find different RAID types based on what amount of drives are used, if reading and writing are both done from all of the drives at the same time, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, etc. According to the exact setup, the error tolerance and the performance could differ.

RAID in Shared Hosting

The revolutionary cloud web hosting platform where all shared hosting accounts are created uses super fast SSD drives rather than the traditional HDDs, and they function in RAID-Z. With this configuration, a number of hard drives work together and at least 1 is a dedicated parity disk. Basically, when data is written on the rest of the drives, it's duplicated 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 some reason, the info can be rebuilt and verified using the parity disk and the data stored on the other ones, thus practically nothing will be lost and there won't be any service disorders. This is an additional level of protection for your data together with the top-notch ZFS file system which uses checksums to make sure that all data on our servers is intact and is not silently corrupted.

RAID in Semi-dedicated Servers

The data uploaded to any semi-dedicated server account is saved on SSD drives which operate in RAID-Z. One of the drives in such a configuration is used for parity - every time data is cloned on it, an additional bit is added. In case a disk happens to be flawed, it will be taken out of the RAID without disturbing the operation of the websites because the data will load from the remaining drives, and when a new drive is added, the data which will be cloned on it will be a combination between the info on the parity disk and data kept on the other hard disks in the RAID. That is done to ensure that the data which is being copied is accurate, so the moment the new drive is rebuilt, it could be integrated into the RAID as a production one. This is an extra guarantee for the integrity of your info since the ZFS file system that runs on our cloud web hosting platform compares a special checksum of all the copies of the files on the separate drives in order to avoid any probability of silent data corruption.