RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which allows a system to take advantage of a number of hard drives as one single logical unit. Put simply, all drives are used as one and the info on all of them is the same. This kind of a setup has two key advantages over using just a single drive to keep data - the first is redundancy, so if one drive stops working, the information will be accessed from the remaining ones, and the second one is better performance because the input/output, or reading/writing operations will be spread among a number of drives. There are different RAID types based on how many drives are employed, whether reading and writing are both handled from all of the drives concurrently, if data is written in blocks on one drive after another or is mirrored between drives in the same time, etc. Determined by the exact setup, the fault tolerance and the performance may vary.
RAID in Cloud Hosting
The cutting-edge cloud web hosting platform where all cloud hosting accounts are created employs fast SSD drives rather than the classic HDDs, and they function in RAID-Z. With this configuration, several hard disks operate together and at least a single one is a dedicated parity disk. Put simply, when data is written on the rest of the drives, it's duplicated on the parity one adding an extra bit. This is carried out for redundancy as even if some drive fails or falls out of the RAID for whatever reason, the info can be rebuilt and verified thanks to the parity disk and the data recorded on the other ones, which means that absolutely nothing will be lost and there will be no service interruptions. This is one more level of security for your info together with the cutting-edge ZFS file system that uses checksums to make sure that all the data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Hosting
The data uploaded to any semi-dedicated hosting account is stored on SSD drives that function in RAID-Z. One of the drives in this kind of a configuration is used for parity - any time data is copied on it, an extra bit is added. If a disk happens to be defective, it will be removed from the RAID without interrupting the functioning of the sites since the data will load from the rest of the drives, and when a new drive is included, the data that will be duplicated on it will be a mix between the info on the parity disk and data kept on the other hard drives in the RAID. That is done in order to guarantee that the data that is being copied is accurate, so as soon as the new drive is rebuilt, it could be included in the RAID as a production one. This is an additional warranty for the integrity of your info because the ZFS file system which runs on our cloud web hosting platform compares a unique checksum of all the copies of the files on the different drives to be able to avoid any chance of silent data corruption.
The SSD drives which we use on the machines where we set up virtual private servers operate in RAID to make sure that any content that you upload will be available and intact at all times. At least 1 drive is used for parity - one bit of information is added to any data copied on it. If a main drive breaks down, it is replaced and the data which will be duplicated on it is calculated between the remaining drives and the parity one. That’s done to ensure that the correct information is copied and that not a single file is corrupted because the new drive will be incorporated into the RAID afterwards. In addition, we use hard disk drives working in RAID on the backup servers, so if you add this upgrade to your VPS plan, you shall use an even more reliable hosting service because your content will be available on multiple drives irrespective of any unexpected hardware failure.