RAID, or Redundant Array of Independent Disks, is a technology of saving data on several hard disks that operate together as one single logical unit. The drives could be physical or logical i.e. in the second case a single drive is split into separate ones via virtualization software. Either way, identical info is stored on all drives and the key benefit of employing this type of a setup is that in the event that a drive stops working, the data will remain available on the other ones. Using a RAID also improves the performance as the input and output operations will be spread among a number of drives. There are several kinds of RAID based on how many drives are used, whether writing is performed on all the drives in real time or just on a single one, and how the info is synchronized between the drives - whether it's recorded in blocks on one drive after another or all of it is mirrored from one on the others. All of these factors show that the fault tolerance and the performance between the different RAID types may vary.
RAID in Shared Hosting
The SSD drives that our cutting-edge cloud web hosting platform uses for storage function in RAID-Z. This type of RAID is intended to work with the ZFS file system that runs on the platform and it uses the so-called parity disk - a special drive where info saved on the other drives is duplicated with an additional bit added to it. If one of the disks stops working, your Internet sites shall continue working from the other ones and once we replace the problematic one, the information that will be copied on it will be rebuilt from what is stored on the rest of the drives along with the information from the parity disk. This is done in order to be able to recalculate the bits of each and every file correctly and to validate the integrity of the info duplicated on the new drive. This is another level of security for the information that you upload to your shared hosting account together with the ZFS file system which analyzes a special digital fingerprint for each and every file on all the drives in real time.
RAID in Semi-dedicated Servers
The RAID type that we employ for the cloud Internet hosting platform where your semi-dedicated server account shall be created is called RAID-Z. What is different about it is that at least one of the disks is used as a parity drive. Simply put, whenever any data is copied on this particular hard drive, one more bit is added to it and if a malfunctioning disk is replaced, the info which will be cloned on it is a mix of the data on the remaining drives in the RAID and that on the parity one. This is done to ensure that your data is intact. Throughout this process, your Internet sites will be up and running normally as RAID-Z allows for an entire drive to fail without service disturbances and it simply uses one of the other ones as the main production drive. Using RAID-Z together with the ZFS file system that uses checksums to ensure that no data will get silently corrupted on our servers, you'll never have to worry about the integrity of your files.
RAID in VPS Servers
The physical servers where we create VPS server work with high-speed SSD drives that will increase the speed of your sites noticeably. The hard drives work in RAID to make sure that you won't lose any info as a result of a power loss or a hardware failure. The production servers employ many different drives where the information is stored and one disk is used for parity i.e. one bit is added to all the information copied on it, which makes it much easier to restore the content without loss in the event a main drive fails. If you pick our backup service, your info will be kept on an individual machine that uses standard hard-disk drives and even though there is no parity one in this case, they are also in a RAID to guarantee that we will have a backup copy of your website content all of the time. With this particular configuration your data will always be safe as it will be available on many drives.