Redundant Array of Independent Disks, or RAID, is a method of storing content on a number of hard disks at the same time. A RAID can be software or hardware based on the HDDs that are used - physical or logical ones, but what’s common between them is that they all work as just a single unit where data is kept. The top advantage of using a RAID is redundancy as the info on all of the drives shall be identical at all times, so even if some drive fails for whatever reason, the information will still be available on the other drives. The overall performance is enhanced as well as the reading and writing processes could be split between multiple drives, so a single one will never be overloaded. There are different kinds of RAIDs where the capabilities and fault tolerance could differ depending on the exact setup - whether data is written on all the drives in real time or it is written on one drive and then mirrored on another, what amount of drives are used for the RAID, and so on.
RAID in Shared Hosting
The SSD drives which our cutting-edge cloud Internet hosting platform uses for storage operate in RAID-Z. This type of RAID is created to work with the ZFS file system that runs on the platform and it works by using the so-called parity disk - a specific drive where info stored on the other drives is cloned with an additional bit added to it. In the event that one of the disks stops working, your Internet sites shall continue working from the other ones and after we replace the problematic one, the info which will be copied on it will be rebuilt from what is stored on the rest of the drives as well as the info from the parity disk. This is performed so as to be able to recalculate the bits of every single file correctly and to verify the integrity of the info duplicated on the new drive. This is one more level of security for the information which you upload to your shared hosting
account together with the ZFS file system that compares a unique digital fingerprint for every single file on all the hard drives in real time.