RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that makes it possible for a system to use multiple hard drives as a single logical unit. In other words, all of the drives are used as one and the information on all of them is identical. This kind of a setup has two huge advantages over using a single drive to store data - the first one is redundancy, so if one drive breaks down, the data will be accessible through the others, and the second one is better performance since the input/output, or reading/writing operations will be distributed among multiple drives. There are different RAID types depending on the number of drives are employed, whether reading and writing are both done from all the drives concurrently, if data is written in blocks on one drive after another or is mirrored between drives in the same time, etcetera. Depending on the particular setup, the fault tolerance and the performance may differ.

RAID in Cloud Hosting

The hard drives that we use for storage with our state-of-the-art cloud hosting platform are not the standard HDDs, but extremely fast solid-state drives (SSD). They operate in RAID-Z - a special setup developed for the ZFS file system that we work with. All of the content that you add to the cloud hosting account will be kept on multiple disk drives and at least one of them will be employed as a parity disk. This is a specific drive where an additional bit is included to any content copied on it. In case a disk in the RAID stops working, it will be changed without service interruptions and the info will be recovered on the new drive by recalculating its bits using the data on the parity disk along with that on the other disks. This is done to guarantee the integrity of the info and together with the real-time checksum authentication which the ZFS file system executes on all drives, you'll never need to concern yourself with the loss of any data no matter what.