RAID, or Redundant Array of Independent Disks, is a technology of storing data on a number hard disk drives which work together as one single logical unit. The drives can be physical or logical i.e. in the aforementioned case one drive is split into independent ones via virtualization software. In either case, the very same information is kept on all of the drives and the key benefit of employing this kind of a setup is that in the event that a drive fails, the data will still be available on the other ones. Using a RAID also boosts the overall performance since the input and output operations will be spread among a couple of drives. There are several types of RAID depending on how many hard disks are used, whether writing is done on all of the drives in real time or just on a single one, and how the data 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 imply that the error tolerance and the performance between the various RAID types can differ.
RAID in Shared Hosting
The SSD drives which our cutting-edge cloud web hosting platform uses for storage function 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 specific drive where info located on the other drives is duplicated with an additional bit added to it. In the event that one of the disks stops functioning, your sites shall continue working from the other ones and after we replace the faulty one, the information which will be cloned on it will be rebuilt from what is stored on the remaining drives along with the information from the parity disk. This is done in order to be able to recalculate the elements of every file properly and to authenticate the integrity of the data copied on the new drive. This is an additional level of security for the info which you upload to your shared hosting account together with the ZFS file system which analyzes a unique digital fingerprint for each and every file on all the disk drives in real time.
RAID in Semi-dedicated Servers
The info uploaded to any semi-dedicated server account is kept on SSD drives which function in RAID-Z. One of the drives in type of a setup is used for parity - whenever data is copied on it, an extra bit is added. In case a disk happens to be problematic, it will be taken out of the RAID without interrupting the work of the Internet sites because the data will load from the remaining drives, and when a new drive is included, the info which will be cloned on it will be a blend between the information on the parity disk and data kept on the other hard disks in the RAID. That is done to guarantee that the data which is being duplicated is accurate, so the moment the new drive is rebuilt, it could be incorporated into the RAID as a production one. This is an extra warranty for the integrity of your info as the ZFS file system which runs on our cloud hosting platform compares a special checksum of all of the copies of your files on the separate drives to avoid any possibility of silent data corruption.
RAID in VPS Servers
The SSD drives which we use on the machines where we generate VPS servers function in RAID to ensure that any content that you upload will be available and intact at all times. At least one drive is used for parity - one bit of data is added to any data cloned on it. In the event that a main drive breaks down, it is replaced and the information which will be copied on it is calculated between the other drives and the parity one. That’s done to ensure that the needed data is copied and that not a single file is corrupted because the new drive will be incorporated into the RAID afterwards. Also, we use hard disks working in RAID on the backup servers, so in case you add this upgrade to your VPS plan, you will use an even more reliable web hosting service because your content will be available on multiple drives irrespective of any sort of unexpected hardware failure.