RAID, or Redundant Array of Independent Disks, is a technology of keeping data on a number hard drives that function together as a single logical unit. The drives can be physical or logical i.e. in the aforementioned case one drive is split into separate ones through virtualization software. In either case, identical data is saved on all drives and the main benefit of using this type of a setup is that in case a drive stops working, the data will remain available on the other ones. Employing a RAID also improves the performance since the input and output operations will be spread among a number of drives. There are several types of RAID dependant upon how many hard drives are used, whether writing is carried out on all of the drives in real time or just on one, and how the data is synced between the hard drives - whether it's written in blocks on one drive after another or it is mirrored from one on the others. These factors show that the error tolerance as well as the performance between the various RAID types can vary.
RAID in Shared Website Hosting
The disk drives that we use for storage with our ground-breaking cloud hosting platform are not the classic HDDs, but super fast solid-state drives (SSD). They function in RAID-Z - a special setup intended for the ZFS file system which we use. Any content that you upload to your shared website hosting account will be kept on multiple drives and at least 1 shall be used as a parity disk. This is a specific drive where an extra bit is included to any content copied on it. In case a disk in the RAID fails, it'll be replaced with no service disruptions and the data will be recovered on the new drive by recalculating its bits thanks to the data on the parity disk along with that on the remaining disks. This is done to guarantee the integrity of the info and together with the real-time checksum validation that the ZFS file system performs on all drives, you will never have to be concerned about losing any data no matter what.
RAID in Semi-dedicated Servers
The info uploaded to any semi-dedicated server account is saved on SSD drives that operate in RAID-Z. One of the drives in this kind of a configuration is used for parity - every time data is cloned on it, an extra bit is added. If a disk happens to be faulty, it will be removed from the RAID without interrupting the operation of the Internet sites as the data will load from the other drives, and when a brand new drive is included, the info that will be duplicated on it will be a mix between the information on the parity disk and data saved on the other drives in the RAID. That is done to ensure that the data which is being copied is accurate, so the moment the new drive is rebuilt, it could be incorporated into the RAID as a production one. This is one more guarantee for the integrity of your info because the ZFS file system which runs on our cloud hosting platform analyzes a unique checksum of all of the copies of your files on the different drives to avoid any possibility of silent data corruption.
RAID in VPS Servers
All VPS server accounts which our company offers are created on physical servers that use SSD drives operating in RAID. At least 1 drive is used for parity - one additional bit is included in the info duplicated on it and in case a main disk stops working, this bit makes it easier to recalculate the bits of the files on the damaged hard disk so that the accurate information is recovered on the new drive added to the RAID. At the same time, your sites will still be online because all the data will still load from at least 1 more hard drive. In case you add routine backups to your VPS package, a copy of your information will be saved on standard hard drives that also work in RAID because we want to make sure that any type of site content you upload will be risk-free all the time. Using multiple hard drives in RAID for all of the main and backup servers allows us to offer fast and reliable web hosting service.