RAID, or Redundant Array of Independent Disks, is a technology of keeping data on several hard disk drives that function together as one logical unit. The drives can be physical or logical i.e. in the second case one single drive is split into independent ones via virtualization software. In any case, the very same data is kept on all the drives and the basic advantage of using such a setup is that in case a drive breaks down, the data shall still be available on the other ones. Using a RAID also improves the overall performance because the input and output operations will be spread among a few drives. There are several types of RAID depending on how many drives are used, whether writing is performed on all drives in real time or just on a single one, and how the info is synchronized between the hard drives - whether it is recorded in blocks on one drive after another or it is mirrored from one on the others. These factors imply that the error tolerance and the performance between the various RAID types could differ.
RAID in Cloud Hosting
Our advanced cloud web hosting platform where all cloud hosting accounts are made uses quick SSD drives instead of the standard HDDs, and they operate in RAID-Z. With this configuration, multiple hard disk drives operate together and at least one is a dedicated parity disk. Put simply, when data is written on the other drives, it is copied on the parity one adding an extra bit. This is done for redundancy as even if a drive fails or falls out of the RAID for whatever reason, the data can be rebuilt and verified using the parity disk and the data stored on the other ones, thus not a single thing will be lost and there won't be any service disorders. This is another level of protection for your data together with the advanced ZFS file system that uses checksums to ensure that all data on our servers is intact and is not silently corrupted.
RAID in Semi-dedicated Hosting
The SSD drives that are used for saving any site content uploaded to the semi-dedicated hosting accounts that we offer operate in RAID-Z. This is a specific setup where one or more drives are employed for parity i.e. the system will include an additional bit to any data copied on this kind of a drive. In case that a disk fails and is substituted with a new one, what data will be copied on the latter will be a mix calculated between the data on the other disks and that on the parity one. This is done to ensure that the info on the new drive shall be accurate. Throughout the procedure, the RAID will continue functioning adequately and the faulty drive will not have an effect on the proper operation of your Internet sites at all. Working with SSDs in RAID-Z is an excellent addition to the ZFS file system that runs on our state-of-the-art cloud platform in terms of preserving the integrity of your files because ZFS uses specific digital identifiers named checksums to avoid silent data corruption.
All virtual private server accounts which our company provides are created on physical servers that take advantage of SSD drives working in RAID. At least one drive is intended for parity - one extra bit is added to the information copied on it and if a main disk stops working, this bit makes it much simpler to recalculate the bits of the files on the damaged disk drive so that the correct information is recovered on the new drive included in the RAID. In the mean time, your sites will remain online because all the info will still load from at least one more drive. In the event that you add regular backups to your VPS plan, a copy of the info will be saved on standard disk drives which also function in RAID as we want to make certain that any content you upload will be protected at all times. Employing multiple hard drives in RAID for all main and backup servers permits us to offer fast and reliable web hosting service.