RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which enables a system to take advantage of a number of hard drives as a single logical unit. In other words, all of the drives are used as one and the info on all of them is identical. Such a configuration has 2 key advantages over using just a single drive to store data - the first one is redundancy, so in the event that one drive doesn't work, the data will be accessed through the remaining ones, and the second one is improved performance as the input/output, or reading/writing operations will be spread among multiple drives. There're different RAID types in accordance with what number of drives are used, if reading and writing are both performed from all of the drives at the same time, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, and many others. According to the particular setup, the error tolerance and the performance could differ.
RAID in Cloud Hosting
The SSD drives that our cutting-edge cloud web hosting platform uses for storage operate in RAID-Z. This kind of RAID is intended to work with the ZFS file system which runs on the platform and it takes advantage of the so-called parity disk - a special drive where info saved on the other drives is cloned with an extra bit added to it. If one of the disks fails, your Internet sites shall continue working from the other ones and as soon as we replace the problematic one, the information that will be duplicated on it will be rebuilt from what is stored on the rest of the drives as well as the information from the parity disk. This is performed so as to be able to recalculate the bits of every single file properly and to verify the integrity of the data cloned on the new drive. This is one more level of security for the content you upload to your cloud hosting account in addition to the ZFS file system which analyzes a unique digital fingerprint for each and every file on all hard drives in real time.
RAID in Semi-dedicated Servers
The info uploaded to any semi-dedicated server account is kept on SSD drives which operate in RAID-Z. One of the drives in such a configuration is used for parity - any time data is copied on it, an additional bit is added. In case a disk turns out to be problematic, it will be taken out of the RAID without interrupting the operation of the sites as the data will load from the remaining drives, and when a brand new drive is included, the information which will be duplicated on it will be a blend between the info on the parity disk and data saved on the other hard disks in the RAID. This is done so as to ensure that the data which is being copied is correct, so as soon as the new drive is rebuilt, it could be included in the RAID as a production one. This is an additional guarantee for the integrity of your data since the ZFS file system that runs on our cloud web hosting platform analyzes a unique checksum of all of the copies of your files on the different drives in order to avoid any chance of silent data corruption.
RAID in VPS Servers
In case you take advantage of one of our VPS server solutions, any content that you upload will be saved on SSD drives that operate in RAID. At least 1 drive is employed for parity so as to guarantee the integrity of the information. In simple terms, this is a special drive where info is copied with one bit added to it. In case a disk in the RAID fails, your Internet sites will continue working and when a new disk replaces the faulty one, the bits of the information that will be duplicated on it are calculated using the healthy and the parity drives. That way, any possibility of corrupting data throughout the process is prevented. We also use standard hard drives that function in RAID for storing backups, so in case you include this service to your VPS plan, your content will be kept on multiple drives and you'll never have to worry about its integrity even in the event of multiple drive failures.