RAID, or Redundant Array of Independent Disks, is a technology for storing data on several hard disk drives that work together as a single logical unit. The drives could be physical or logical i.e. in the aforementioned case a single drive is split into separate ones through virtualization software. Either way, the very same data is stored on all drives and the main advantage of employing this type of a setup is that if a drive breaks down, the data shall still be available on the other ones. Having a RAID also improves the performance because the input and output operations will be spread among several drives. There are several types of RAID dependant upon how many hard drives are used, whether writing is done on all drives in real time or just on one, and how the info is synced between the hard drives - whether it is recorded in blocks on one drive after another or all of it is mirrored from one on the others. All these factors mean that the fault tolerance and the performance between the different RAID types can differ.
RAID in Shared Web Hosting
All the content that you upload to your new shared web hosting account will be held on fast SSD drives that function in RAID-Z. This setup is built to use the ZFS file system that runs on our cloud web hosting platform and it adds one more level of protection for your site content on top of the real-time checksum validation which ZFS uses to ensure the integrity of the data. With RAID-Z, the information is stored on several disks and at least one of them is a parity disk - whenever information is written on it, an extra bit is added, so in case any drive fails for some 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 functioning efficiently until the faulty drive is replaced and the information is synchronized on it.
RAID in Semi-dedicated Servers
The RAID type that we use for the cloud 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 employed as a parity drive. Put simply, whenever any data is duplicated on this specific disk drive, one more bit is added to it and if a problematic disk is replaced, the info that will be copied on it is a combination 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 data is intact. Throughout this process, your websites will be working normally as RAID-Z allows for a whole drive to fail without causing any service interruptions and it simply works by using one of the other ones as the main production drive. Using 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 have to worry about the integrity of your files.
RAID in VPS Servers
All VPS server accounts that our company provides are created on physical servers that use SSD drives operating in RAID. At least one drive is intended for parity - one additional bit is included in the information duplicated on it and in case a main disk fails, this bit makes it much simpler to recalculate the bits of the files on the damaged drive so that the right information is restored on the new drive added to the RAID. In the mean time, your Internet sites will remain online as all the information will still load from at least one other disk drive. In case you add regular backups to your VPS plan, a copy of the information will be stored on standard hard drives which also work in RAID because we want to make sure that any kind of content you upload will be safe and sound all the time. Working with multiple hard drives in RAID for all of the main and backup servers enables us to offer fast and reliable hosting service.