Redundant Array of Independent Disks, or RAID, is a method of keeping content on several hard drives at the same time. A RAID might be software or hardware based on the hard drives which are used - physical or logical ones, but what’s common between them is that they all perform as just one single unit where information is kept. The top advantage of employing a RAID is redundancy as the information on all drives is exactly the same all the time, so even in the event that one of the drives fails for some reason, the info will still be present on the other drives. The general performance is also better because the reading and writing processes could be split between multiple drives, so a single one won't be overloaded. There are different types of RAIDs where the functionality and fault tolerance can vary according to the particular setup - whether information is written on all the drives real-time or it is written on a single drive and then mirrored on another, what number of drives are used for the RAID, etc.
RAID in Shared Web Hosting
The hard disks that we employ for storage with our outstanding cloud web hosting platform are not the standard HDDs, but high-speed solid-state drives (SSD). They function in RAID-Z - a special setup intended for the ZFS file system that we use. All the content that you upload to your shared web hosting account will be kept on multiple hard disks and at least one of them will be employed as a parity disk. This is a special drive where a further bit is included to any content copied on it. In case a disk in the RAID stops working, it will be replaced without 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 other disks. This is done to guarantee the integrity of the info and along with the real-time checksum validation that the ZFS file system runs on all drives, you will never need to worry about losing any data no matter what.
RAID in Semi-dedicated Servers
The info uploaded to any semi-dedicated server account is kept on SSD drives that operate in RAID-Z. One of the drives in type of a configuration is used for parity - every time data is copied on it, an additional bit is added. If a disk turns out to be problematic, it will be removed from the RAID without interrupting the work of the websites as the data will load from the other drives, and when a new drive is added, the data that will be copied on it will be a combination between the information on the parity disk and data saved on the other drives in the RAID. This is done in order to guarantee that the data which is being duplicated is correct, so the moment the new drive is rebuilt, it could be integrated into the RAID as a production one. This is an extra guarantee for the integrity of your data as the ZFS file system which runs on our cloud hosting platform analyzes a special checksum of all the copies of the files on the various drives in order to avoid any chance of silent data corruption.
RAID in VPS Servers
The physical servers where we generate VPS server employ quick SSD drives that will increase the speed of your sites considerably. The hard drives work in RAID to ensure that you won't lose any information because of a power loss or a hardware breakdown. The production servers work with a variety of drives where the information is kept and one disk is used for parity i.e. one bit is added to all data copied on it, which makes it much easier to recover the site content without any loss if a main drive fails. If you use our backup service, your information will be stored on an individual machine that uses standard hard-disk drives and 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 of your content all of the time. With this setup your information will always be safe as it will be available on many disk drives.