RAID, or Redundant Array of Independent Disks, is a technology for saving data on multiple hard disk drives that function together as a single logical unit. The drives can be physical or logical i.e. in the latter case a single drive is split into separate ones through virtualization software. Either way, exactly the same information is stored on all the drives and the basic advantage of using this type of a setup is that in case a drive breaks down, the data will remain available on the remaining ones. Employing a RAID also enhances the performance since the input and output operations will be spread among a couple of drives. There are several kinds of RAID depending on how many drives are used, whether writing is done on all of the drives in real time or just on one, and how the information is synchronized between the hard drives - whether it is recorded in blocks on one drive after another or all of it is mirrored from one on the others. These factors imply that the fault tolerance and the performance between the various RAID types can differ.
RAID in Cloud Hosting
The SSD drives that our cutting-edge cloud hosting platform uses for storage function in RAID-Z. This sort of RAID is designed to work with the ZFS file system that runs on the platform and it works by using the so-called parity disk - a special drive where information saved on the other drives is copied with an additional bit added to it. If one of the disks stops functioning, your sites shall continue working from the other ones and once we replace the problematic one, the information which will be cloned on it will be rebuilt from what is stored on the other drives together with the info from the parity disk. This is performed so as to be able to recalculate the bits of each and every file adequately and to confirm the integrity of the info duplicated on the new drive. This is another level of security for the information which you upload to your cloud hosting account along with the ZFS file system that analyzes a unique digital fingerprint for every single file on all of the drives in real time.