Redundant Array of Independent Disks, or RAID, is a way of saving content on multiple hard disks at the same time. A RAID can be software or hardware depending on the hard drives that are used - physical or logical ones, however what is common between them is the fact that they all work as just a single unit where info is kept. The top advantage of employing a RAID is redundancy as the info on all the drives shall be exactly the same at all times, so even if a drive fails for some reason, the info will still be available on the other drives. The general performance is also enhanced since the reading and writing processes will be split between different drives, so a single one will not be overloaded. There are different types of RAIDs where the effectiveness and fault tolerance may differ depending on the exact setup - whether data is written on all of the drives real-time or it's written on a single drive and then mirrored on another, what amount of drives are used for the RAID, and many others.
RAID in Cloud Hosting
The SSD drives which our cutting-edge cloud Internet hosting platform uses for storage work in RAID-Z. This sort of RAID is designed to work with the ZFS file system that runs on the platform and it uses the so-called parity disk - a special drive where info kept on the other drives is duplicated with an extra bit added to it. In the event that one of the disks fails, your sites shall continue working from the other ones and as soon as we replace the bad one, the info that will be copied on it will be rebuilt from what is stored on the rest of the drives together with the info from the parity disk. This is done so as to be able to recalculate the bits of every single file correctly and to authenticate the integrity of the information cloned on the new drive. This is another level of security for the information that you upload to your cloud hosting account in addition to the ZFS file system which compares a unique digital fingerprint for each file on all disk drives in real time.
RAID in Semi-dedicated Servers
The information 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 - each time data is copied on it, an additional bit is added. If a disk turns out to be faulty, it will be taken out of the RAID without disturbing the operation of the sites because the data will load from the remaining drives, and when a new drive is included, the data that will be duplicated on it will be a combination between the data on the parity disk and data kept on the other hard drives in the RAID. This is done to guarantee that the data that is being cloned is correct, so as soon as the new drive is rebuilt, it could be incorporated 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 web hosting platform analyzes a special checksum of all copies of your files on the various drives to avoid any probability of silent data corruption.
RAID in VPS Servers
The physical servers where we create VPS server employ quick SSD drives that will increase the speed of your sites substantially. The disk drives function in RAID to ensure that you won't lose any data as a result of a power loss or a hardware malfunction. The production servers use many different drives where the information is stored and one disk is used for parity i.e. one bit is added to all the information copied on it, that makes it much easier to restore the site content without loss in case a main drive fails. In case you use our backup service, the data will be saved on a separate 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 ensure that we will have a backup copy of your site content at all times. With this setup your information will always be safe since it will be available on multiple drives.