RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard disks which operate together as a single logical unit. The drives could be physical or logical i.e. in the aforementioned case one drive is split into individual ones using virtualization software. In either case, identical info is saved on all of the drives and the basic benefit of using this kind of a setup is that in the event that a drive stops working, the data shall still be available on the other ones. Employing a RAID also enhances the performance because the input and output operations will be spread among several drives. There are several types of RAID depending on how many drives are used, whether writing is done on all drives in real time or just on one, and how the info is synced between the hard 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 mean that the fault tolerance and the performance between the different RAID types may differ.
RAID in Shared Website Hosting
Any content that you upload to your new shared website hosting account will be placed on fast SSD drives which operate in RAID-Z. This configuration is built to use the ZFS file system which runs on our cloud Internet hosting platform and it adds one more level of protection for your website content in addition to the real-time checksum authentication that ZFS uses to ensure the integrity of the data. With RAID-Z, the info is stored on a couple of disks and at least 1 is a parity disk - whenever information is written on it, an additional bit is added, so if any drive fails for some reason, the integrity of the info can be verified by recalculating its bits based on what is saved on the production hard disks and on the parity one. With RAID-Z, the functioning of our system won't be interrupted and it will continue working flawlessly until the faulty drive is changed and the info is synced on it.
RAID in Semi-dedicated Hosting
The RAID type that we use for the cloud hosting platform where your semi-dedicated hosting account shall be created is named RAID-Z. What's different about it is that at least one of the disks is used as a parity drive. Put simply, whenever any data is copied on this special disk drive, one more bit is added to it and in the event that a defective disk is replaced, the data that will be duplicated on it is a mix of the data on the remaining hard drives in the RAID and that on the parity one. We do this to make sure that the info is intact. Throughout this process, your sites will be up and running normally because RAID-Z makes it possible for an entire drive to fail without service interruptions and it simply uses one of the remaining ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to guarantee that no data will get silently corrupted on our servers, you won't ever have to worry about the integrity of your files.