RAID, or Redundant Array of Independent Disks, is a technology for saving data on several hard disks which operate together as one logical unit. The drives could be physical or logical i.e. in the latter case one single drive is split into separate ones via virtualization software. Either way, exactly the same information is stored on all drives and the key advantage of using this kind of a setup is that in the event that a drive fails, the data shall still be available on the remaining ones. Employing a RAID also enhances the performance since the input and output operations will be spread among a couple of drives. There are several kinds of RAID depending on how many hard drives are used, whether writing is done on all the drives in real time or just on a single one, and how the information is synced between the drives - whether it's recorded in blocks on one drive after another or it is mirrored from one on the others. These factors show that the fault tolerance as well as the performance between the different RAID types could differ.
RAID in Web Hosting
Our state-of-the-art cloud web hosting platform where all web hosting accounts are made employs fast SSD drives as an alternative to the classic HDDs, and they operate in RAID-Z. With this configuration, numerous hard drives function together and at least one is a dedicated parity disk. Put simply, when data is written on the other drives, it is copied on the parity one adding an extra bit. This is performed for redundancy as even if a drive fails or falls out of the RAID for whatever reason, the info can be rebuilt and verified using the parity disk and the data recorded on the other ones, which means that not a single thing will be lost and there will be no service interruptions. This is one more level of security for your information in addition to the top-notch ZFS file system that uses checksums to ensure that all of the data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Hosting
The RAID type that we employ for the cloud Internet hosting platform where your semi-dedicated hosting account shall be created is referred to as RAID-Z. What's different about it is that at least one of the disks is used as a parity drive. Put simply, whenever any kind of data is cloned on this particular drive, one more bit is included to it and in case a problematic disk is changed, the data that will be copied on it is a combination of the data on the other hard disks in the RAID and that on the parity one. This is done to guarantee that the data is intact. Throughout this process, your sites will be functioning normally since RAID-Z enables a whole drive to fail without any service interruptions and it simply works by using one of the remaining ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to guarantee that no data can get silently corrupted on our servers, you'll never have to worry about the integrity of your files.