RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that makes it possible for a system to use several hard drives as a single logical unit. Put simply, all drives are used as one and the data on all of them is identical. This kind of a configuration has two key advantages over using just a single drive to store data - the first is redundancy, so in the event that one drive fails, the data will be accessible from the others, and the second is improved performance as the input/output, or reading/writing operations will be spread among multiple drives. You can find different RAID types depending on what amount of drives are used, if reading and writing are both executed from all drives concurrently, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. Depending on the particular setup, the fault tolerance and the performance could differ.
RAID in Web Hosting
The SSD drives which our cutting-edge cloud web hosting platform employs for storage work in RAID-Z. This type 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 duplicated with an additional bit added to it. If one of the disks stops functioning, your sites will continue working from the other ones and once we replace the bad one, the info which will be copied on it will be recovered from what is stored on the remaining drives together with the data from the parity disk. This is done so as to be able to recalculate the bits of every single file adequately and to validate the integrity of the info duplicated on the new drive. This is another level of security for the info that you upload to your web hosting account together with the ZFS file system that analyzes a special digital fingerprint for every single file on all the disk drives in real time.
RAID in Semi-dedicated Hosting
The RAID type which we employ for the cloud hosting platform where your semi-dedicated hosting account shall be created is called RAID-Z. What is different about it is that at least one of the disks is used as a parity drive. In simple terms, whenever any kind of data is duplicated on this particular drive, one more bit is included to it and if a faulty disk is changed, the data that will be cloned on it is a combination of the data on the remaining disk drives in the RAID and that on the parity one. This is done to guarantee that the data is intact. Throughout this process, your sites will be working normally since RAID-Z allows for an entire drive to fail without any service disruptions and it simply works by using one of the other ones as the main production drive. Employing RAID-Z together with the ZFS file system which uses checksums to ensure that no data shall get silently corrupted on our servers, you won't ever have to worry about the integrity of your files.
The physical servers where we make virtual private server work with extremely fast SSD drives which will increase the speed of your sites considerably. The hard disks operate in RAID to guarantee that you won't lose any info due to a power loss or a hardware malfunction. The production servers take advantage of multiple drives where the info is stored and one disk is used for parity i.e. one bit is added to all data copied on it, that makes it much easier to restore the website content without any loss in the event a main drive fails. If you choose our backup service, your info will be stored on an individual machine that uses standard hard-disk drives and though there's no parity one in this case, they are also in a RAID to make sure that we will have a backup copy of your content all the time. With this type of configuration your info will always be safe because it will be available on several disk drives.