Redundant Array of Independent Disks, or RAID, is a way of storing content on several hard disk drives at the same time. A RAID could be software or hardware depending on the HDDs which are used - physical or logical ones, still what is common between them is the fact that they all operate as a single unit where data is stored. The biggest advantage of employing a RAID is redundancy since the data on all the drives is exactly the same all the time, so even in the event that one of the drives fails for some reason, the data will still be available on the remaining drives. The overall performance is also enhanced since the reading and writing processes will be split between multiple drives, so a single one won't be overloaded. There are different types of RAIDs where the capabilities and fault tolerance can vary depending on the exact setup - whether info is written on all the drives in real time or it's written on a single drive and then mirrored on another, what amount of drives are used for the RAID, etc.
RAID in Shared Hosting
The advanced cloud hosting platform where all shared hosting accounts are made uses super fast SSD drives instead of the classic HDDs, and they function in RAID-Z. With this setup, multiple hard disks operate together and at least one of them is a dedicated parity disk. Put simply, when data is written on the rest of the drives, it's copied on the parity one adding an extra bit. This is performed for redundancy as even in case some drive fails or falls out of the RAID for whatever reason, the info can be rebuilt and verified using the parity disk and the data stored on the other ones, thus practically nothing will be lost and there will not be any service interruptions. This is another level of security for your information in addition to the top-notch ZFS file system which uses checksums to ensure that all of the data on our servers is undamaged and is not silently corrupted.
RAID in Semi-dedicated Hosting
The data uploaded to any semi-dedicated hosting account is stored on SSD drives that function in RAID-Z. One of the drives in this kind of a configuration is used for parity - each time data is cloned on it, an additional bit is added. In case a disk happens to be defective, it will be removed from the RAID without disturbing the work of the Internet sites because the data will load from the remaining drives, and when a new drive is included, the information that will be cloned on it will be a combination between the data on the parity disk and data saved on the other hard disks in the RAID. That is done so as to ensure that the information that is being copied is accurate, so as soon as the new drive is rebuilt, it could be included in the RAID as a production one. This is one more warranty for the integrity of your information because the ZFS file system which runs on our cloud web hosting platform compares a unique checksum of all the copies of the files on the various drives so as to avoid any probability of silent data corruption.
RAID in VPS Hosting
The physical servers where we generate virtual private server employ fast SSD drives which will boost the speed of your websites substantially. The disk drives function in RAID to guarantee that you won't lose any info due to a power loss or a hardware malfunction. The production servers use multiple drives where the information is saved and one disk is used for parity i.e. one bit is added to all of the info copied on it, which makes it much easier to recover the content without any loss in the event a main drive fails. If you use our backup service, your data will be kept on an independent machine that uses standard hard-disk drives and even though there's no parity one in this case, they are also in a RAID to make sure that we will have a backup of your website content at all times. With this particular configuration your data will always be safe as it will be available on a lot of drives.