RAID, or Redundant Array of Independent Disks, is a technology for keeping data on several hard disk drives which operate together as a single logical unit. The drives could be physical or logical i.e. in the aforementioned case one single drive is split into different ones using virtualization software. In either case, identical info is saved on all of the drives and the main benefit of using this type of a setup is that if a drive breaks down, the data will still be available on the remaining ones. Having a RAID also enhances the overall performance because the input and output operations will be spread among a couple of drives. There are several types of RAID based on how many hard drives are used, whether writing is carried out on all of the drives in real time or just on a single one, and how the data 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 of these factors suggest that the error tolerance and the performance between the different RAID types may vary.
RAID in Shared Web Hosting
Our advanced cloud hosting platform where all shared web hosting accounts are created uses fast SSD drives as opposed to the classic HDDs, and they function in RAID-Z. With this configuration, numerous hard disk drives operate together and at least one of them is a dedicated parity disk. Put simply, when data is written on the other drives, it's cloned on the parity one adding an extra bit. This is carried out for redundancy as even in case some drive fails or falls out of the RAID for some reason, the information can be rebuilt and verified using the parity disk and the data saved on the other ones, so not a thing will be lost and there will be no service disturbances. This is another level of security for your data along with the state-of-the-art ZFS file system which uses checksums to guarantee that all the data on our servers is intact and is not silently corrupted.
RAID in Semi-dedicated Hosting
The SSD drives which are used for keeping any site content uploaded to the semi-dedicated hosting accounts which we provide work in RAID-Z. This is a special configuration where one or more hard drives are used for parity i.e. the system will add an extra bit to any data cloned on this kind of a disk drive. In the event that a disk fails and is substituted with another one, what info will be cloned on the latter will be a mix calculated between the data on the remaining drives and that on the parity one. This is done to ensure that the data on the new drive shall be accurate. During the process, the RAID will continue functioning adequately and the faulty drive will not impact the normal operation of your Internet sites in any way. Using SSDs in RAID-Z is a superb addition to the ZFS file system which runs on our revolutionary cloud platform in terms of preserving the integrity of your files because ZFS uses specific digital identifiers referred to as checksums in order to prevent silent data corruption.
RAID in VPS Web Hosting
The SSD drives that we use on the physical machines where we set up virtual private servers work in RAID to make sure that any content that you upload will be available and intact all the time. At least a single drive is used for parity - one bit of info is added to any data copied on it. If a main drive breaks down, it is replaced and the info which will be duplicated on it is calculated between the rest of the drives and the parity one. It's done this way to make sure that the correct information is copied and that no file is corrupted since the new drive will be incorporated into the RAID afterwards. Also, we use hard disks functioning in RAID on the backup servers, so if you add this upgrade to your VPS plan, you'll use an even more reliable web hosting service because your content will be available on multiple drives irrespective of any sort of unexpected hardware malfunction.