RAID, or Redundant Array of Independent Disks, is a technology for saving data on several hard disks that operate together as one single logical unit. The drives could be physical or logical i.e. in the aforementioned case a single drive is divided into different ones via virtualization software. In either case, the same data is saved on all of the drives and the key benefit of employing this type of a setup is that if a drive stops working, the data shall still be available on the remaining ones. Using a RAID also improves the overall performance as the input and output operations will be spread among several drives. There are several kinds of RAID depending on how many hard disks are used, whether writing is carried out on all the drives in real time or just on a single one, and how the info is synced between the drives - whether it is recorded in blocks on one drive after another or it is mirrored from one on the others. All these factors imply that the error tolerance as well as the performance between the various RAID types can vary.
RAID in Shared Hosting
The state-of-the-art cloud Internet hosting platform where all shared hosting accounts are created employs quick SSD drives as opposed to the classic HDDs, and they work in RAID-Z. With this configuration, numerous hard disk drives operate together and at least one is a dedicated parity disk. Simply put, when data is written on the rest of the drives, it is duplicated on the parity one adding an extra bit. This is performed for redundancy as even in case a drive fails or falls out of the RAID for some reason, the information 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 won't be any service disturbances. This is one more level of protection for your information in addition to the revolutionary ZFS file system which uses checksums to ensure that all data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Servers
In case you host your Internet sites within a semi-dedicated server account from our firm, all the content that you upload will be stored on SSD drives which work in RAID-Z. With this form of RAID, at least 1 of the hard disks is used for parity - when data is synced between the drives, an extra bit is added to it on the parity one. The reasoning behind this is to ensure the integrity of the info that is cloned to a brand new drive in case one of the drives in the RAID fails as the website content being copied on the brand new disk is recalculated from the info on the standard disk drives and on the parity one. An additional advantage of RAID-Z is the fact that even in the event that a hard drive stops functioning, the system could switch to another one right away without service disruptions of any sort. RAID-Z adds an additional level of safety for the content that you upload on our cloud hosting platform in addition to the ZFS file system that uses unique checksums so as to validate the integrity of each file.
RAID in VPS Servers
The physical servers where we create VPS server use fast SSD drives which will increase the speed of your sites considerably. The disk drives work in RAID to make sure that you won't lose any info due to a power loss or a hardware malfunction. The production servers work with a variety of drives where the data is saved and one disk is used for parity i.e. one bit is added to all the data copied on it, which makes it easier to recover the website content without loss if a main drive fails. If you take advantage of our backup service, the data will be stored on an independent machine which uses standard hard-disk drives and even though there isn't a parity one in this case, they are also in a RAID to make sure that we will have a backup copy of your site content all the time. With this configuration your information will always be safe because it will be available on several disk drives.