RAID, or Redundant Array of Independent Disks, is a technology of storing data on a number hard disk drives which operate together as one logical unit. The drives could be physical or logical i.e. in the latter case one single drive is divided into independent ones using virtualization software. Either way, exactly the same information is stored on all of the drives and the basic advantage of using this type of a setup is that in the event that a drive stops working, the data shall still be available on the other ones. Using a RAID also enhances the overall performance as the input and output operations will be spread among a few drives. There are several types of RAID based on how many hard disks are used, whether writing is performed on all the drives in real time or just on one, and how the info is synced between the drives - whether it is written in blocks on one drive after another or it is mirrored from one on the others. All these factors suggest that the fault tolerance and the performance between the various RAID types may differ.
RAID in Cloud Hosting
Any content which you upload to your new cloud hosting
account will be held on quick 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 security for your website content in addition to the real-time checksum authentication which ZFS uses to guarantee the integrity of the data. With RAID-Z, the information is stored on a number of disks and at least one of them is a parity disk - whenever information is written 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 kept on the production drives and on the parity one. With RAID-Z, the operation of our system will never be interrupted and it'll continue working smoothly until the problematic drive is changed and the info is synced on it.
RAID in Semi-dedicated Servers
The RAID type which we employ for the cloud hosting platform where your semi-dedicated server
account shall be created is referred to as RAID-Z. What's 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 duplicated on this special disk drive, one more bit is added to it and in the event that a faulty disk is replaced, the information that will be copied on it is a mix of the data on the remaining drives in the RAID and that on the parity one. We do this to ensure that the data is intact. Throughout this process, your sites will be working normally because RAID-Z makes it possible for a whole drive to fail without any service disturbances and it simply uses one of the other ones as the main production drive. Using RAID-Z together with the ZFS file system that uses checksums to guarantee that no data shall get silently corrupted on our servers, you won't need to worry about the integrity of your files.
RAID in VPS Servers
All VPS server
accounts which our company offers are made on physical servers which employ SSD drives operating in RAID. At least 1 drive is used for parity - one additional bit is included in the information copied on it and in case a main disk breaks down, this bit makes it much simpler to recalculate the bits of the files on the failed disk drive so that the accurate information is recovered on the new drive added to the RAID. At the same time, your Internet sites will still be online since all the data will still load from at least 1 more disk drive. In case you add regular backups to your VPS package, a copy of the data will be kept on standard hard disks that also operate in RAID since we would like to make sure that any sort of website content you upload will be protected all of the time. Using multiple hard disks in RAID for all the main and backup servers enables us to offer fast and reliable Internet hosting service.