Redundant Array of Independent Disks, or RAID, is a method of saving content on a number of hard disk drives simultaneously. A RAID can be software or hardware depending on the drives that are used - physical or logical ones, still what’s common between them is the fact that they all operate as a single unit where info is stored. The main advantage of using a RAID is redundancy as the data on all the drives will be exactly the same all the time, so even if one of the drives fails for some reason, the info will still be present on the other drives. The overall performance is also better because the reading and writing processes can be split between multiple drives, so a single one will never be overloaded. There're different kinds of RAIDs where the capabilities and fault tolerance can vary depending on the exact setup - whether info is written on all drives real-time or it's written on a single drive and afterwards mirrored on another, what number of drives are used for the RAID, etc.
RAID in Cloud Hosting
The drives that we use for storage with our outstanding cloud web hosting platform are not the classic HDDs, but super fast solid-state drives (SSD). They operate in RAID-Z - a special setup created for the ZFS file system which we employ. All the content that you add to your cloud hosting account will be saved on multiple disk drives and at least one shall be used as a parity disk. This is a special drive where an additional bit is added to any content copied on it. In the event that a disk in the RAID stops working, it will be replaced with no service disturbances and the info will be rebuilt on the new drive by recalculating its bits thanks to the data on the parity disk along with that on the other disks. This is done to guarantee the integrity of the info and along with the real-time checksum validation which the ZFS file system runs on all drives, you will never have to worry about the loss of any info no matter what.
RAID in Semi-dedicated Hosting
The RAID type that we employ for the cloud hosting platform where your semi-dedicated hosting account will be created is referred to as 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 data is duplicated on this specific drive, one more bit is added to it and if a malfunctioning disk is changed, the info that will be copied on it is a combination of the data on the remaining drives in the RAID and that on the parity one. It's done this way to make sure that your information is intact. During this process, your sites will be working normally because RAID-Z allows 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 which uses checksums to warrant that no data will get silently corrupted on our servers, you'll never have to worry about the integrity of your files.
RAID in VPS Web Hosting
The SSD drives which we use on the machines where we create virtual private servers operate in RAID to make sure that any content that you upload will be available and intact at all times. At least a single drive is employed for parity - one bit of information is added to any data copied on it. If a main drive stops working, it is changed and the info that will be duplicated on it is calculated between the other drives and the parity one. That’s done to make sure that the correct information is copied and that no file is corrupted as the new drive will be included in the RAID afterwards. Also, we use hard drives working in RAID on the backup servers, so if you add this upgrade to your VPS package, you shall use an even more reliable Internet hosting service because your content will be available on multiple drives regardless of any unexpected hardware malfunction.