RAID, which is an acronym of Redundant Array of Independent Disks, is a software or hardware storage virtualization technology that allows a system to use several hard drives as one single logical unit. Simply put, all drives are used as one and the data on all of them is identical. Such a setup has 2 major advantages over using a single drive to save data - the first is redundancy, so if one drive doesn't work, the information will be accessible from the others, and the second one is better performance since the input/output, or reading/writing operations will be distributed among multiple drives. You can find different RAID types based on what number of drives are employed, if reading and writing are both handled from all the drives at the same time, if data is written in blocks on one drive after another or is mirrored between drives in the same time, and so on. According to the particular setup, the error tolerance and the performance could differ.
RAID in Website Hosting
All the content which you upload to your new website hosting account will be placed on quick SSD drives which function in RAID-Z. This setup is built to employ the ZFS file system which runs on our cloud web hosting platform and it adds an additional level of protection for your content in addition to the real-time checksum verification which ZFS uses to guarantee the integrity of the data. With RAID-Z, the info is stored on a number of disks and at least one of them is a parity disk - whenever data is written on it, an extra bit is added, so in case any drive stops functioning for whatever reason, the stability of the information can be verified by recalculating its bits in accordance with what is stored on the production hard disks and on the parity one. With RAID-Z, the functioning of our system won't be interrupted and it will continue working flawlessly until the malfunctioning drive is changed and the information is synced on it.
RAID in Semi-dedicated Servers
The RAID type that we employ for the cloud hosting platform where your semi-dedicated server account shall be created is referred to as RAID-Z. What is different about it is that at least one of the disks is used as a parity drive. Put simply, whenever any data is copied on this specific hard drive, one more bit is added to it and in the event that a defective disk is changed, the information which will be cloned on it is a mix of the data on the remaining hard drives in the RAID and that on the parity one. It's done this way to guarantee that the information is intact. During this process, your websites will be working normally because RAID-Z allows for a whole drive to fail without any service disturbances and it simply uses one of the remaining ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to warrant that no data can get silently corrupted on our servers, you won't ever have to worry about the integrity of your files.
RAID in VPS Servers
The SSD drives which we use on the physical machines where we generate VPS servers operate in RAID to make sure that any content that you upload will be available and intact all of the time. At least one drive is employed for parity - one bit of info is added to any data copied on it. In the event that a main drive stops working, it is replaced and the info which will be duplicated on it is calculated between the rest of the drives and the parity one. That’s done to ensure that the required data is copied and that not a single file is corrupted since the new drive will be a part of the RAID afterwards. We also use hard disk drives operating in RAID on the backup servers, so in case you add this upgrade to your VPS package, you'll use an even more reliable web hosting service because your content will be available on multiple drives irrespective of any unexpected hardware malfunction.