Redundant Array of Independent Disks, or RAID, is a method of saving content on a number of hard drives at the same time. A RAID might be software or hardware based on the hard drives that are used - physical or logical ones, but what’s common between them is that they all perform as just one single unit where data is kept. The key advantage of employing a RAID is redundancy as the information on all of the drives shall be the same all of the time, so even in case a drive fails for some reason, the info will still be present on the remaining drives. The overall performance will also improve because the reading and writing processes will be split between a number of drives, so a single one won't be overloaded. There're different sorts of RAIDs where the functionality and fault tolerance may differ based on the particular setup - whether data is written on all drives real-time or it's written on a single drive and afterwards mirrored on another, what amount of drives are used for the RAID, and so on.
RAID in Hosting
The SSD drives that our cutting-edge cloud Internet hosting platform employs for storage operate in RAID-Z. This type of RAID is created to work with the ZFS file system that runs on the platform and it employs the so-called parity disk - a special drive where data kept on the other drives is cloned with an additional bit added to it. If one of the disks stops working, your Internet sites will continue working from the other ones and once we replace the bad one, the information that will be cloned on it will be recovered from what is stored on the remaining drives together with the data from the parity disk. This is done in order to be able to recalculate the elements of each and every file adequately and to confirm the integrity of the information copied on the new drive. This is an additional level of security for the information that you upload to your hosting account together with the ZFS file system which compares a special digital fingerprint for each file on all hard drives in real time.
All virtual private server accounts which our company offers are made on physical servers which take advantage of SSD drives functioning in RAID. At least one drive is employed for parity - one additional bit is included in the information cloned on it and in case a main disk breaks down, this bit makes it easier to recalculate the bits of the files on the damaged disk drive so that the right info is restored on the new drive added to the RAID. In the mean time, your Internet sites will still be online because all the information will still load from at least 1 other drive. If you add regular backups to your VPS package, a copy of the info will be kept on standard hard disks which also operate in RAID since we would like to make certain that any type of content you add will be protected all of the time. Working with multiple drives in RAID for all of the main and backup servers allows us to offer fast and reliable Internet hosting service.