Redundant Array of Independent Disks, or RAID, is a way of storing content on multiple hard disks simultaneously. A RAID can be software or hardware based on the HDDs which are used - physical or logical ones, yet what’s common between them is that they all operate as a single unit where information is kept. The main advantage of using a RAID is redundancy as the info on all the drives shall be the same at all times, so even in case a drive fails for whatever reason, the info will still be present on the other drives. The general performance is also better as the reading and writing processes could be split between various drives, so a single one will not be overloaded. There are different types of RAIDs where the efficiency and fault tolerance could differ according to the specific setup - whether information is written on all drives in real time or it's written on a single drive and after that mirrored on another, what amount of drives are used for the RAID, etc.
RAID in Shared Website Hosting
The cutting-edge cloud Internet hosting platform where all shared website hosting accounts are created employs fast SSD drives as opposed to the traditional HDDs, and they function in RAID-Z. With this setup, a number of hard drives work together and at least one is a dedicated parity disk. In simple terms, when data is written on the other drives, it's duplicated on the parity one adding an extra bit. This is done for redundancy as even in case some drive fails or falls out of the RAID for some reason, the information can be rebuilt and verified thanks to the parity disk and the data saved on the other ones, therefore practically nothing will be lost and there will not be any service interruptions. This is another level of security for your data together with the state-of-the-art ZFS file system that 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 RAID type that we use for the cloud hosting platform where your semi-dedicated hosting account shall be created is named RAID-Z. What is different about it is that at least one of the disks is used as a parity drive. Simply put, whenever any data is copied on this specific disk drive, one more bit is added to it and in the event that a faulty disk is replaced, the info which will be duplicated on it is a combination of the data on the remaining hard disks in the RAID and that on the parity one. It's done this way to make sure that the info is intact. During this process, your sites will be working normally as RAID-Z allows for a whole drive to fail without service interruptions and it simply works by using one of the other ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to warrant that no data will get silently corrupted on our servers, you'll never need to worry about the integrity of your files.