Redundant Array of Independent Disks, or RAID, is a way of keeping content on a number of hard disks at the same time. A RAID could be software or hardware depending on the hard drives that are used - physical or logical ones, however what is common between them is that they all work as just one single unit where data is kept. The main advantage of using a RAID is redundancy as the data on all of the drives will be the same all the time, so even in the event that a drive fails for some reason, the information will still be available on the rest of the drives. The general performance is also enhanced since the reading and writing processes can be split between different drives, so a single one will not be overloaded. There're different sorts of RAIDs where the effectiveness and fault tolerance may vary depending on the specific setup - whether information is written on all drives in real time or it's written on a single drive and then mirrored on another, what amount of drives are used for the RAID, etc.
RAID in Shared Hosting
The hard disks that we employ for storage with our revolutionary cloud web hosting platform are not the classic HDDs, but high-speed NVMes. They work in RAID-Z - a special setup designed for the ZFS file system which we use. Any content that you upload to the shared hosting account will be stored on multiple hard drives and at least one shall be employed as a parity disk. This is a special drive where an additional bit is included to any content copied on it. If a disk in the RAID stops functioning, it will be replaced without any service disturbances and the data will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk along with that on the remaining disks. This is done in order to ensure the integrity of the data and along with the real-time checksum validation which the ZFS file system executes on all drives, you'll never need to worry about the loss of any data no matter what.
RAID in Semi-dedicated Servers
The information uploaded to any semi-dedicated server account is saved on NVMe drives which operate in RAID-Z. One of the drives in this kind of a setup is used for parity - whenever data is cloned on it, an additional bit is added. If a disk happens to be problematic, it will be removed from the RAID without disturbing the operation of the sites because the data will load from the other drives, and when a new drive is added, the data which will be cloned on it will be a combination between the data on the parity disk and data saved on the other hard disks in the RAID. That is done so as to guarantee that the information that is being cloned is accurate, so once the new drive is rebuilt, it could be incorporated into the RAID as a production one. This is an extra warranty for the integrity of your information since the ZFS file system which runs on our cloud Internet hosting platform compares a special checksum of all the copies of the files on the different drives so as to avoid any chance of silent data corruption.
RAID in VPS Servers
The physical servers where we create VPS server employ high-speed NVMe drives that will raise the speed of your sites substantially. The hard disks operate in RAID to guarantee that you won't lose any data because of a power loss or a hardware breakdown. The production servers employ a variety of drives where the information is stored and one disk is used for parity i.e. one bit is added to all the info copied on it, which makes it much easier to restore the content without loss if a main drive breaks down. If you pick our backup service, your info will be stored on an independent machine which uses standard hard-disk drives and though there is no parity one in this case, they are also in a RAID to ensure that we will have a backup copy of your site content all the time. With this type of configuration your info will always be safe as it will be available on several disk drives.