RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that enables a system to take advantage of multiple hard drives as a single logical unit. In other words, all of the drives are used as one and the data on all of them is the same. This type of a configuration has 2 huge advantages over using just a single drive to store data - the first is redundancy, so in case one drive stops working, the information will be accessed from the remaining ones, and the second one is better performance since the input/output, or reading/writing operations will be spread among a number of drives. You can find different RAID types depending on how many drives are employed, if reading and writing are both executed from all of the drives concurrently, whether data is written in blocks on one drive after another or is mirrored between drives in the same time, etcetera. Determined by the exact setup, the error tolerance and the performance could differ.
RAID in Hosting
The disk drives which we employ for storage with our ground-breaking cloud Internet hosting platform are not the standard HDDs, but high-speed solid-state drives (SSD). They operate in RAID-Z - a special setup designed for the ZFS file system that we use. Any content that you add to your hosting account will be held on multiple disk drives and at least 1 will be used as a parity disk. This is a specific drive where an additional bit is added to any content copied on it. In the event that a disk in the RAID fails, it'll be replaced with no service disruptions and the information will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk along with that on the other disks. This is done to ensure the integrity of the data and together with the real-time checksum authentication which the ZFS file system executes on all drives, you will never have to be concerned about the loss of any data no matter what.
RAID in Semi-dedicated Hosting
In case you host your Internet sites in a semi-dedicated hosting account from our firm, any content which you upload will be kept on SSD drives that work in RAID-Z. With this kind of RAID, at least 1 of the hard disks is employed for parity - when data is synchronized between the hard drives, an additional bit is included in it on the parity one. The reasoning behind this is to guarantee the integrity of the info that is copied to a new drive in the event that one of the disks in the RAID breaks down because the site content being copied on the brand new disk is recalculated from the data on the standard drives and on the parity one. An additional advantage of RAID-Z is the fact that even in case a hard drive fails, the system can switch to another one immediately without service disturbances of any sort. RAID-Z adds an additional level of security for the content you upload on our cloud Internet hosting platform along with the ZFS file system that uses unique checksums so as to authenticate the integrity of each and every file.
The physical servers where we generate virtual private server work with quick SSD drives that will increase the speed of your Internet sites noticeably. The hard drives function in RAID to guarantee that you won't lose any data because of a power loss or a hardware failure. The production servers take advantage of many different drives where the data is stored and one disk is used for parity i.e. one bit is added to all information copied on it, that makes it much easier to restore the website content without any loss if a main drive breaks down. In case you use our backup service, your info will be stored on an individual machine which uses standard hard-disk drives and despite the fact that there is no parity one in this case, they are also in a RAID to guarantee that we will have a backup of your site content all of the time. With this configuration your info will always be safe because it will be available on several disk drives.