RAID, or Redundant Array of Independent Disks, is a technology for storing data on several hard disk drives which function together as one single logical unit. The drives can be physical or logical i.e. in the aforementioned case a single drive is divided into different ones using virtualization software. In any case, the same information is stored on all drives and the basic benefit of employing this type of a setup is that if a drive stops working, the data will remain available on the other ones. Employing a RAID also boosts the overall performance since the input and output operations will be spread among a few drives. There are several types of RAID dependant upon how many drives are used, whether writing is performed on all the drives in real time or just on one, and how the data is synced between the hard drives - whether it's written in blocks on one drive after another or it is mirrored from one on the others. These factors imply that the error tolerance and the performance between the various RAID types can differ.
RAID in Cloud Web Hosting
The SSD drives that our cutting-edge cloud Internet hosting platform uses for storage work in RAID-Z. This sort 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 information located on the other drives is duplicated with an additional bit added to it. If one of the disks fails, your Internet sites shall continue working from the other ones and once we replace the faulty one, the information that will be copied 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 performed so as to be able to recalculate the bits of each and every file adequately and to authenticate the integrity of the information duplicated on the new drive. This is an additional level of security for the information you upload to your cloud web hosting account together with the ZFS file system that analyzes a unique digital fingerprint for each and every file on all of the disk drives in real time.
RAID in Semi-dedicated Hosting
The RAID type that we use for the cloud hosting platform where your semi-dedicated hosting account shall be created is named RAID-Z. What is different about it is that at least 1 of the disks is employed as a parity drive. Simply put, whenever any kind of data is duplicated on this particular disk drive, one more bit is included to it and in case a problematic disk is changed, the info that will be cloned on it is a mix of the data on the other disk drives in the RAID and that on the parity one. This is done to guarantee that the information is intact. Throughout this process, your sites will be working normally as RAID-Z enables a whole drive to fail without service interruptions and it simply works by using one of the other ones as the main production drive. Using RAID-Z together with the ZFS file system which uses checksums to guarantee that no data will get silently corrupted on our servers, you will not have to worry about the integrity of your files.
RAID in VPS
The SSD drives that we use on the physical machines where we create virtual private servers work in RAID to make sure that any content you upload will be available and intact at all times. At least a single drive is employed for parity - one bit of info is added to any data copied on it. In the event that a main drive breaks down, it is changed and the information which will be cloned on it is calculated between the rest of the drives and the parity one. That’s done to ensure that the needed info is copied and that no file is corrupted since the new drive will be included in the RAID afterwards. In addition, we use hard disks operating in RAID on the backup servers, so in case you add this upgrade to your VPS package, you'll use an even more reliable web hosting service since your content will be available on multiple drives regardless of any type of unpredicted hardware malfunction.