Redundant Array of Independent Disks, or RAID, is a way of keeping content on several hard drives simultaneously. A RAID might be software or hardware depending on the hard drives which are used - physical or logical ones, however what’s common between them is that they all perform as one single unit where your information is kept. The main advantage of using a RAID is redundancy as the info on all of the drives is identical at all times, so even in the event that some drive fails for whatever reason, the info will still be available on the other drives. The general performance is also enhanced because the reading and writing processes will be split between a number of drives, so a single one will not be overloaded. There are different kinds of RAIDs where the efficiency and fault tolerance may vary based on the particular setup - whether data is written on all the drives in real time or it is written on a single drive and afterwards mirrored on another, the number of drives are used for the RAID, etcetera.
RAID in Shared Hosting
The SSD drives which our cutting-edge cloud Internet hosting platform uses for storage work in RAID-Z. This type of RAID is created to work with the ZFS file system which runs on the platform and it uses the so-called parity disk - a specific drive where data stored on the other drives is copied with an extra bit added to it. If one of the disks fails, your sites shall continue working from the other ones and once we replace the bad one, the data that will be copied 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 performed so as to be able to recalculate the bits of each file correctly and to confirm the integrity of the data copied on the new drive. This is one more level of security for the information that you upload to your shared hosting account together with the ZFS file system that compares a special digital fingerprint for each file on all the hard drives in real time.