RAID, which stands short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that enables a system to use many hard drives as one single logical unit. In other words, all the drives are used as one and the info on all of them is identical. Such a setup has 2 key advantages over using a single drive to keep data - the first one is redundancy, so in case one drive fails, the info will be accessed from the remaining ones, and the second one is better performance since the input/output, or reading/writing operations will be distributed among a number of drives. There're different RAID types based on the number of drives are used, whether reading and writing are both executed from all drives simultaneously, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and many others. According to the particular setup, the fault tolerance and the performance may vary.
RAID in Shared Hosting
All the content that you upload to your new shared hosting account will be saved on fast SSD drives that operate in RAID-Z. This setup is built to work with the ZFS file system that runs on our cloud web hosting platform and it adds another level of security for your content on top of the real-time checksum verification which ZFS uses to guarantee the integrity of the data. With RAID-Z, the data is stored on several disks and at least 1 is a parity disk - whenever data is recorded on it, an additional bit is added, so if any drive fails for whatever reason, the integrity of the data can be verified by recalculating its bits in accordance with what is saved on the production hard disks and on the parity one. With RAID-Z, the operation of our system will not be interrupted and it'll continue working effectively until the malfunctioning drive is changed and the info is synced on it.
RAID in Semi-dedicated Hosting
The RAID type which we employ for the cloud Internet hosting platform where your semi-dedicated hosting account will be created is referred to as RAID-Z. What is different about it is that at least 1 of the disks is employed as a parity drive. In simple terms, whenever any kind of data is duplicated on this particular hard drive, one more bit is added to it and in case a faulty disk is replaced, the info which will be cloned on it is a combination of the data on the remaining hard disks in the RAID and that on the parity one. This is done to guarantee that the info is intact. During this process, your sites will be working normally since RAID-Z allows for an entire drive to fail without service disturbances and it simply uses one of the remaining ones as the main production drive. Using RAID-Z together with the ZFS file system that uses checksums to guarantee that no data can get silently corrupted on our servers, you'll never need to worry about the integrity of your files.
RAID in VPS Web Hosting
The physical servers where we make virtual private server work with fast SSD drives that will boost the speed of your websites substantially. The drives function in RAID to guarantee that you won't lose any data because of a power loss or a hardware malfunction. The production servers take advantage of many different drives where the info is kept and one disk is used for parity i.e. one bit is added to all of the information copied on it, which makes it much easier to recover the content without any loss if a main drive fails. In case you use our backup service, your info will be stored 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 make sure that we will have a backup of your website content all the time. With this setup your data will always be safe as it will be available on many drives.