RAID, or Redundant Array of Independent Disks, is a technology of saving data on several hard disks that operate together as one logical unit. The drives could be physical or logical i.e. in the aforementioned case a single drive is split into separate ones using virtualization software. Either way, the same info is kept on all drives and the main advantage of employing this type of a setup is that in case a drive stops working, 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 couple of drives. There are several kinds of RAID based on how many drives are used, whether writing is done on all of the drives in real time or just on a single one, and how the information is synced between the hard drives - whether it is 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 fault tolerance and the performance between the different RAID types may vary.
RAID in Cloud Hosting
The SSD drives that our cutting-edge cloud web hosting platform uses for storage operate in RAID-Z. This type of RAID is designed to work with the ZFS file system that runs on the platform and it employs the so-called parity disk - a special drive where info stored on the other drives is copied with an additional bit added to it. If one of the disks fails, your websites will continue working from the other ones and after we replace the faulty one, the info which will be duplicated on it will be recovered from what is stored on the rest of the drives together with the info from the parity disk. This is done so as to be able to recalculate the bits of each file properly and to verify the integrity of the information copied on the new drive. This is one more level of security for the content which you upload to your cloud hosting account in addition to the ZFS file system which compares a unique digital fingerprint for every single file on all of the drives in real time.
RAID in Semi-dedicated Servers
The RAID type which we use 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. Simply put, whenever any kind of data is cloned on this specific drive, one more bit is added to it and in the event that a problematic disk is changed, the information that will be duplicated on it is a combination of the data on the other drives in the RAID and that on the parity one. This is done to make sure that your data is intact. Throughout this process, your Internet sites will be working normally since RAID-Z allows for an entire drive to fail without service interruptions 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 warrant that no data can get silently corrupted on our servers, you will not need to worry about the integrity of your files.
RAID in VPS Servers
The physical servers where we create VPS server use high-speed SSD drives that will raise the speed of your Internet sites substantially. The drives operate in RAID to guarantee that you will not lose any info because of a power loss or a hardware malfunction. The production servers work with a variety of drives where the data is stored and one disk is used for parity i.e. one bit is added to all info copied on it, that makes it much easier to recover the content without loss if a main drive fails. If you choose our backup service, the info will be kept on an independent machine that uses standard hard-disk drives and even though there's no parity one in this case, they are also in a RAID to make sure that we will have a backup of your site content all the time. With this particular configuration your info will always be safe because it will be available on several disk drives.