RAID, or Redundant Array of Independent Disks, is a technology for keeping data on multiple hard drives that function together as one single logical unit. The drives could be physical or logical i.e. in the aforementioned case one drive is split into different ones using virtualization software. Either way, the same info is stored on all drives and the basic advantage of using such a setup is that in case a drive stops working, the data shall still be available on the remaining ones. Having a RAID also boosts the performance as the input and output operations will be spread among a number of drives. There are several kinds of RAID depending on how many hard drives are used, whether writing is performed on all the drives in real time or just on a single one, and how the data is synchronized between the drives - whether it is written in blocks on one drive after another or it is mirrored from one on the others. These factors show that the error tolerance and the performance between the different RAID types could differ.
RAID in Cloud Website Hosting
All of the content which you upload to your new cloud website hosting
account will be placed on fast SSD drives that function in RAID-Z. This configuration is built to work with the ZFS file system which runs on our cloud web hosting platform and it adds another level of protection for your site content in addition to the real-time checksum validation that ZFS uses to ensure the integrity of the data. With RAID-Z, the data is stored on a number of disks and at least 1 is a parity disk - whenever info is recorded on it, an additional bit is added, so in the event that any drive stops functioning for whatever reason, the integrity of the data can be verified by recalculating its bits based on what is stored on the production hard drives and on the parity one. With RAID-Z, the functioning of our system won't be interrupted and it'll continue working effectively until the problematic drive is replaced and the information is synchronized on it.
RAID in VPS Web Hosting
The SSD drives that we use on the physical machines where we set up virtual private servers
operate in RAID to ensure that any content you upload will be available and intact all of the time. At least a single drive is used for parity - one bit of info is added to any data cloned 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. It's done this way to ensure that the correct info 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 drives operating in RAID on the backup servers, so in the event that you add this upgrade to your VPS plan, you shall use an even more reliable hosting service as your content will be available on multiple drives irrespective of any unforeseen hardware malfunction.