RAID, or Redundant Array of Independent Disks, is a technology for saving data on several hard disk drives that function together as a single logical unit. The drives can be physical or logical i.e. in the second case a single drive is divided into separate ones through virtualization software. In either case, the same data is stored on all the drives and the key advantage of using such a setup is that if a drive fails, the data will still be available on the remaining ones. Using a RAID also enhances the performance since the input and output operations will be spread among a number of drives. There are several kinds of RAID based on how many hard drives are used, whether writing is carried out on all drives in real time or just on one, and how the info is synced between the drives - whether it's written in blocks on one drive after another or all of it is mirrored from one on the others. All these factors show that the fault tolerance and the performance between the various RAID types can differ.

RAID in Shared Hosting

Our state-of-the-art cloud hosting platform where all shared hosting accounts are created employs fast SSD drives as an alternative to the traditional HDDs, and they operate in RAID-Z. With this setup, several hard disks operate together and at least a single one 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 done for redundancy as even in case some drive fails or falls out of the RAID for some reason, the data can be rebuilt and verified thanks to the parity disk and the data recorded on the other ones, therefore not a thing will be lost and there will be no service disturbances. This is an additional level of security for your information in addition to the state-of-the-art ZFS file system that uses checksums to make sure that all of the data on our servers is undamaged and is not silently corrupted.

RAID in Semi-dedicated Servers

The RAID type which we use for the cloud Internet hosting platform where your semi-dedicated server account will be created is named RAID-Z. What is different about it is that at least one of the disks is employed as a parity drive. Simply put, whenever any data is duplicated on this specific drive, one more bit is included to it and in case a problematic disk is replaced, the data which will be duplicated on it is a combination of the data on the remaining hard disks in the RAID and that on the parity one. This is done to ensure that your info is intact. During this process, your sites will be working normally since RAID-Z makes it possible for a whole drive to fail without any service interruptions and it simply works by using one of the other ones as the main production drive. Using RAID-Z together with the ZFS file system that uses checksums to ensure that no data shall get silently corrupted on our servers, you will not need to worry about the integrity of your files.