RAID, or Redundant Array of Independent Disks, is a technology of keeping data on multiple hard disk drives that work together as one single logical unit. The drives could be physical or logical i.e. in the aforementioned case one single drive is split into independent ones using virtualization software. Either way, the very same information is stored on all of the drives and the main benefit of employing this type of a setup is that in the event that a drive fails, the data shall still be available on the other ones. Employing a RAID also enhances the overall performance as the input and output operations will be spread among a number of drives. There are several kinds of RAID dependant upon how many drives are used, whether writing is done on all of the drives in real time or just on one, and how the data is synchronized between the hard drives - whether it is written in blocks on one drive after another or all of it is mirrored from one on the others. All these factors imply that the fault tolerance and the performance between the different RAID types may differ.
RAID in Shared Hosting
The hard drives which we use for storage with our ground-breaking cloud Internet hosting platform are not the traditional HDDs, but fast solid-state drives (SSD). They work in RAID-Z - a special setup created for the ZFS file system that we employ. Any content that you add to your shared hosting account will be held on multiple disk drives and at least one will be employed as a parity disk. This is a special drive where a further bit is added to any content copied on it. In case a disk in the RAID stops functioning, it'll be replaced without any service interruptions 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 other disks. This is done so as to ensure the integrity of the info and together with the real-time checksum verification which the ZFS file system performs on all drives, you'll never need to worry about the loss of any data no matter what.
RAID in Semi-dedicated Servers
If you host your sites in a semi-dedicated server account from our firm, all of the content you upload will be held on SSD drives which operate in RAID-Z. With this type of RAID, at least 1 of the drives is employed for parity - when data is synced between the drives, an extra bit is included in it on the parity one. The purpose behind this is to ensure the integrity of the info which is copied to a new drive if one of the disks in the RAID stops working because the website content being copied on the new disk is recalculated from the information on the standard hard drives and on the parity one. Another advantage of RAID-Z is the fact that even if a disk drive fails, the system can switch to another one promptly without service interruptions of any kind. RAID-Z adds an additional level of security for the content which you upload on our cloud web hosting platform together with the ZFS file system which uses unique checksums in order to validate the integrity of each and every file.
RAID in VPS Servers
In case you use one of our VPS server solutions, any content which you upload will be saved on SSD drives that function in RAID. At least 1 drive is used for parity so as to guarantee the integrity of the information. In simple terms, this is a special drive where information is copied with one bit added to it. In case a disk inside the RAID stops working, your sites will continue working and when a new disk replaces the defective one, the bits of the information that will be duplicated on it are calculated by using the healthy and the parity drives. This way, any probability of corrupting data throughout the process is averted. We also employ regular hard disks that function in RAID for storing backups, so should you include this service to your VPS package, your website content will be kept on multiple drives and you won't ever have to worry about its integrity even in the event of multiple drive breakdowns.