Redundant Array of Independent Disks, or RAID, is a way of saving content on several hard disk drives concurrently. A RAID could be software or hardware depending on the drives which are used - physical or logical ones, however what’s common between them is the fact that they all work as just one single unit where data is saved. The biggest advantage of using a RAID is redundancy since the information on all of the drives shall be identical at all times, so even if one of the drives fails for some reason, the information will still be available on the rest of the drives. The general performance is also better since the reading and writing processes can be split between different drives, so a single one won't be overloaded. There are different sorts of RAIDs where the performance and fault tolerance may differ according to the exact setup - whether your data is written on all of the 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, and so on.
RAID in Shared Hosting
The hard drives which we use for storage with our revolutionary cloud hosting platform are not the standard HDDs, but fast solid-state drives (SSD). They work in RAID-Z - a special setup developed for the ZFS file system which we work with. Any content that you upload to your shared hosting account will be saved on multiple disk drives and at least one will 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'll be changed with no service disturbances and the information will be rebuilt on the new drive by recalculating its bits using the data on the parity disk plus that on the other disks. This is done in order to guarantee the integrity of the data and together with the real-time checksum authentication that the ZFS file system executes on all drives, you won't ever need to be concerned about losing any data no matter what.
RAID in Semi-dedicated Servers
The RAID type that we use for the cloud web hosting platform where your semi-dedicated server account shall be created is known as RAID-Z. What's different about it is that at least one of the disks is used as a parity drive. Put simply, whenever any kind of data is duplicated on this special hard drive, one more bit is included to it and in the event that a faulty disk is replaced, the info which will be duplicated on it is a combination of the data on the remaining hard disks in the RAID and that on the parity one. This is done to ensure that your info is intact. During this process, your websites will be functioning normally since RAID-Z makes it possible for an entire drive to fail without service disturbances and it simply works by using one of the remaining ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to warrant that no data shall get silently corrupted on our servers, you will not have to worry about the integrity of your files.
RAID in VPS Servers
If you employ one of our VPS server solutions, any content which you upload will be kept on SSD drives that function in RAID. At least a single drive is employed for parity so as to guarantee the integrity of the information. In simple terms, this is a special drive where data is copied with one bit added to it. In case a disk inside the RAID breaks down, your sites will continue working and when a new disk substitutes the faulty one, the bits of the info that will be copied on it are calculated by using the healthy and the parity drives. By doing this, any probability of corrupting data throughout the process is averted. We also use regular hard drives which work in RAID for storing backup copies, so in case you add this service to your VPS plan, your content will be stored on multiple drives and you will never need to worry about its integrity even in the event of multiple drive breakdowns.