RAID, which is short for Redundant Array of Independent Disks, is a software or hardware storage virtualization technology which enables a system to employ several hard drives as a single logical unit. Simply put, all the drives are used as one and the data on all of them is the same. Such a configuration has two major advantages over using a single drive to save data - the first one is redundancy, so in case one drive fails, the data will be accessible through the remaining ones, and the second one is improved performance since the input/output, or reading/writing operations will be spread among different drives. You can find different RAID types depending on how many drives are employed, whether reading and writing are both handled from all the drives concurrently, whether 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 exact setup, the fault tolerance and the performance vary.
RAID in Website Hosting
Any content which you upload to your new website hosting
account will be placed on fast SSD drives which work in RAID-Z. This configuration is built to use the ZFS file system that runs on our cloud Internet hosting platform and it adds one more level of protection for your website content in addition to the real-time checksum verification which ZFS uses to ensure the integrity of the data. With RAID-Z, the data is stored on a number of disks and at least one is a parity disk - whenever information is written on it, an extra bit is added, so in the event that any drive stops working for some reason, the integrity of the information can be verified by recalculating its bits in accordance with what is stored on the production disks and on the parity one. With RAID-Z, the operation of our system will never be interrupted and it will continue operating effectively until the problematic drive is replaced and the data is synced on it.
RAID in Semi-dedicated Servers
The RAID type which we use for the cloud web hosting platform where your semi-dedicated server
account will 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. In simple terms, whenever any kind of data is cloned on this particular hard drive, one more bit is added to it and in case a malfunctioning disk is replaced, the data which will be copied on it is a mix of the data on the remaining disk drives in the RAID and that on the parity one. It's done this way to guarantee that your data is intact. Throughout this process, your websites will be functioning normally because RAID-Z makes it possible for an entire drive to fail without service disturbances and it simply uses one of the other ones as the main production drive. Employing RAID-Z together with the ZFS file system that uses checksums to guarantee that no data shall get silently corrupted on our servers, you'll never need to worry about the integrity of your files.