RAID, or Redundant Array of Independent Disks, is a technology of storing data on multiple hard drives which operate together as a single logical unit. The drives could be physical or logical i.e. in the second case one single drive is divided into different ones through virtualization software. In any case, the same information is kept on all of the drives and the key advantage of using this type of a setup is that if a drive breaks down, the data shall still be available on the other ones. Having a RAID also improves the performance as the input and output operations will be spread among several drives. There are several types of RAID dependant upon how many drives are used, whether writing is carried out on all drives in real time or just on a single one, and how the information is synchronized between the hard drives - whether it is recorded in blocks on one drive after another or it is mirrored from one on the others. All these factors suggest that the fault tolerance as well as the performance between the different RAID types can vary.
RAID in Web Hosting
The cutting-edge cloud web hosting platform where all web hosting
accounts are created employs super fast SSD drives as an alternative to the traditional HDDs, and they work in RAID-Z. With this setup, multiple hard disk drives operate together and at least 1 is a dedicated parity disk. Basically, when data is written on the remaining drives, it's copied on the parity one adding an extra bit. This is carried out for redundancy as even if a drive fails or falls out of the RAID for some reason, the information can be rebuilt and verified thanks to the parity disk and the data recorded on the other ones, therefore nothing will be lost and there won't be any service interruptions. This is an additional level of protection for your information together with the revolutionary ZFS file system which uses checksums to ensure that all the data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Servers
The SSD drives which are used for saving any site content uploaded to the semi-dedicated server
accounts which we offer function in RAID-Z. This is a special setup where one or more drives are employed for parity i.e. the system will include an additional bit to any data duplicated on such a hard drive. If a disk fails and is replaced with a new one, what info will be cloned on the latter shall be a mix calculated between the data on the other disks and that on the parity one. This is done to make sure that the info on the new drive shall be accurate. During the procedure, the RAID will continue working adequately and the problematic drive won't affect the proper operation of your websites by any means. Using SSDs in RAID-Z is a great addition to the ZFS file system which runs on our advanced cloud platform with regards to preserving the integrity of your files as ZFS uses special digital identifiers identified as checksums to avoid silent data corruption.
RAID in VPS Servers
The SSD drives which we use on the physical machines where we generate VPS servers
work in RAID to make sure that any content that you upload will be available and intact at all times. At least a single drive is used for parity - one bit of data is added to any data cloned on it. In the event that a main drive fails, it is replaced and the information which will be copied on it is calculated between the rest of the drives and the parity one. That’s done to ensure that the required info is copied and that not a single file is corrupted as the new drive will be included in the RAID afterwards. Also, we use hard drives functioning in RAID on the backup servers, so in the event that you add this upgrade to your VPS plan, you'll use an even more reliable Internet hosting service since your content will be available on multiple drives regardless of any kind of sudden hardware failure.