RAID, or Redundant Array of Independent Disks, is a technology for keeping data on multiple hard disk drives that function 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. Either way, exactly the same info is stored on all drives and the basic benefit of employing this type of a setup is that in the event that a drive breaks down, the data will still be available on the other ones. Employing a RAID also improves the overall performance because the input and output operations will be spread among a number of drives. There are several types of RAID based on how many drives are used, whether writing is done on all of the drives in real time or just on one, and how the data is synced between the drives - whether it is written in blocks on one drive after another or all of it is mirrored from one on the others. All these factors indicate that the fault tolerance and the performance between the different RAID types may differ.
RAID in Cloud Hosting
The disk drives that we employ for storage with our state-of-the-art cloud hosting platform are not the classic HDDs, but high-speed solid-state drives (SSD). They function in RAID-Z - a special setup developed for the ZFS file system which we work with. All the content that you upload to your cloud hosting account will be held on multiple hard drives and at least 1 shall be used as a parity disk. This is a special drive where an extra bit is added to any content copied on it. If a disk in the RAID fails, it will be changed with no service disturbances and the information will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk plus that on the remaining disks. This is done so as to ensure the integrity of the information and together with the real-time checksum verification which the ZFS file system performs on all drives, you will never have to worry about the loss of any data no matter what.
RAID in Semi-dedicated Servers
In case you host your websites in a semi-dedicated server account from our firm, any content you upload will be kept on SSD drives which operate in RAID-Z. With this form of RAID, at least one of the disks is employed for parity - when data is synced between the hard drives, an additional bit is added to it on the parity one. The reasoning behind this is to guarantee the integrity of the data that is duplicated to a brand new drive if one of the hard drives in the RAID fails because the content being copied on the new disk is recalculated from the data on the standard disk drives and on the parity one. An additional advantage of RAID-Z is that even in the event that a disk drive stops functioning, the system could switch to another one promptly without service disruptions of any sort. RAID-Z adds an additional level of security for the content you upload on our cloud hosting platform in addition to the ZFS file system which uses unique checksums to verify the integrity of each and every file.
RAID in VPS Servers
The SSD drives that we use on the machines where we generate VPS servers function in RAID to make sure that any content you upload will be available and intact all of the time. At least a single drive is employed for parity - one bit of info is added to any data copied on it. In case a main drive stops working, it is replaced and the information that will be cloned on it is calculated between the other drives and the parity one. This is done to ensure that the needed info is copied and that not a single file is corrupted since the new drive will be included in the RAID afterwards. Also, we use hard drives working in RAID on the backup servers, so in case you add this upgrade to your VPS package, you will use an even more reliable Internet hosting service since your content will be available on multiple drives irrespective of any type of unforeseen hardware failure.