RAID, or Redundant Array of Independent Disks, is a technology of storing data on a number hard disk drives that work together as one single logical unit. The drives can be physical or logical i.e. in the second case one single drive is divided into different ones through virtualization software. In either case, exactly the same information is saved on all drives and the main advantage of using this kind of a setup is that if a drive stops working, the data shall still be available on the other ones. Having a RAID also enhances the performance because the input and output operations will be spread among a couple of drives. There are several types 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 information is synchronized between the hard drives - whether it's recorded in blocks on one drive after another or all of it is mirrored from one on the others. All these factors suggest that the error tolerance as well as the performance between the different RAID types may vary.
RAID in Cloud Web Hosting
The SSD drives that our cutting-edge cloud Internet hosting platform employs for storage operate in RAID-Z. This sort of RAID is developed to work with the ZFS file system that runs on the platform and it takes advantage of the so-called parity disk - a special drive where info kept on the other drives is copied with an additional bit added to it. In case one of the disks fails, your sites will continue working from the other ones and after we replace the problematic one, the data which will be duplicated on it will be rebuilt from what is stored on the other drives as well as the info from the parity disk. This is done so as to be able to recalculate the elements of each and every file adequately and to confirm the integrity of the data duplicated on the new drive. This is one more level of security for the info you upload to your cloud web hosting
account in addition to the ZFS file system that compares a unique 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 hosting platform where your semi-dedicated server
account will be created is called RAID-Z. What's different about it is that at least one of the disks is employed as a parity drive. Put simply, whenever any kind of data is cloned on this specific disk drive, one more bit is added to it and in the event that a problematic disk is changed, the info which will be copied on it is a mix of the data on the other drives in the RAID and that on the parity one. We do this to ensure that the data is intact. Throughout this process, your Internet sites will be functioning normally since RAID-Z enables an entire drive to fail without any service disturbances and it simply works by using one of the remaining ones as the main production drive. Using RAID-Z together with the ZFS file system which uses checksums to guarantee that no data can get silently corrupted on our servers, you won't need to worry about the integrity of your files.
RAID in VPS Servers
In case you use one of our VPS server
plans, any content which you upload will be stored on SSD drives that work in RAID. At least 1 drive is intended for parity so as to ensure the integrity of your info. In simple terms, this is a special drive where data is copied with one bit added to it. If a disk from the RAID breaks down, your sites will continue working and when a new disk replaces the faulty one, the bits of the data that will be cloned on it are calculated by using the healthy and the parity drives. That way, any potential for corrupting data throughout the process is avoided. We also use ordinary hard disk drives that operate in RAID for storing backup copies, so should you add this service to your VPS plan, your content will be saved on multiple drives and you'll never have to worry about its integrity even in the event of multiple drive failures.