RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which allows a system to employ a number of hard drives as a single logical unit. To put it differently, all of the drives are used as one and the info on all of them is identical. This type of a configuration has two key advantages over using a single drive to save data - the first is redundancy, so in the event that one drive fails, the info will be accessible from the others, and the second is improved performance because the input/output, or reading/writing operations will be spread among several drives. There're different RAID types depending on how many drives are used, if reading and writing are both done from all drives simultaneously, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. Based on the exact setup, the fault tolerance and the performance vary.
RAID in Shared Website Hosting
The SSD drives that our cutting-edge cloud web hosting platform uses for storage operate in RAID-Z. This sort of RAID is designed to work with the ZFS file system which runs on the platform and it uses the so-called parity disk - a specific drive where information kept on the other drives is cloned with an extra bit added to it. If one of the disks stops working, your sites will continue working from the other ones and once we replace the bad one, the info which will be cloned on it will be rebuilt from what is stored on the remaining drives along with the data from the parity disk. This is performed so as to be able to recalculate the elements of every file correctly and to validate the integrity of the information cloned on the new drive. This is one more level of security for the information that you upload to your shared website hosting
account along with the ZFS file system that analyzes a special digital fingerprint for each file on all the hard drives in real time.
RAID in Semi-dedicated Hosting
The RAID type which we use for the cloud Internet hosting platform where your semi-dedicated hosting
account shall 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. In simple terms, whenever any data is copied on this special hard drive, one more bit is included to it and if a defective disk is replaced, the information that will be duplicated on it is a combination of the data on the remaining disk drives in the RAID and that on the parity one. We do this to ensure that your data is intact. During this process, your sites will be functioning normally as RAID-Z makes it possible for a whole drive to fail without causing any service disruptions 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 warrant that no data shall get silently corrupted on our servers, you won't need to worry about the integrity of your files.
RAID in VPS Web Hosting
The SSD drives which we use on the physical machines where we set up virtual private servers
work in RAID to ensure that any content you upload will be available and intact all of the time. At least one drive is used for parity - one bit of data is added to any data copied on it. If a main drive stops working, it is changed and the information that will be copied on it is calculated between the other drives and the parity one. It's done this way to make sure that the right information is copied and that not a single file is corrupted as the new drive will be incorporated into the RAID afterwards. Also, we use hard disk drives operating in RAID on the backup servers, so in case you add this upgrade to your VPS package, you will use an even more reliable hosting service as your content will be available on multiple drives regardless of any type of sudden hardware failure.