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 take advantage of a number of hard drives as a single logical unit. Put simply, all the drives are used as one and the info on all of them is identical. Such a setup has two huge advantages over using just a single drive to store data - the first is redundancy, so in the event that one drive breaks down, the information will be accessible through the others, and the second one is better performance as the input/output, or reading/writing operations will be spread among different drives. There're different RAID types depending on what number of drives are used, if reading and writing are both handled 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. According to the exact setup, the error tolerance and the performance may differ.

RAID in Shared Website Hosting

The SSD drives which our cutting-edge cloud Internet hosting platform employs for storage operate in RAID-Z. This sort of RAID is intended to work with the ZFS file system which runs on the platform and it uses the so-called parity disk - a special drive where data kept on the other drives is copied with an additional bit added to it. In case one of the disks stops working, your sites will continue working from the other ones and once we replace the problematic one, the information which will be duplicated on it will be rebuilt from what is stored on the rest of the drives together with the information from the parity disk. This is done in order to be able to recalculate the bits of each and every file correctly and to validate the integrity of the info cloned on the new drive. This is another level of security for the content which you upload to your shared website hosting account along with the ZFS file system that analyzes a unique digital fingerprint for every single file on all the hard drives in real time.

RAID in VPS

The SSD drives which we use on the physical machines where we create 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 1 drive is used for parity - one bit of info is added to any data cloned on it. In case a main drive fails, it is changed and the info that will be duplicated on it is calculated between the rest of the drives and the parity one. That’s done to make sure that the needed info is copied and that not a single file is corrupted since the new drive will be a part of the RAID afterwards. Also, we use hard drives 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 since your content will be available on multiple drives regardless of any sort of sudden hardware failure.