RAID 5

RAID 5 can be seen as a RAID 0 stripe set with continuous parity: The data is also written in strips over all data carriers involved, whereby one data block always contains the parity data. A RAID 5 storage requires at least three hard disks, whereby the capacity of the volume is calculated with the capacity of all used hard disks minus one. So if four 3 TB hard drives are involved, this results in a total capacity of 9 TB for the RAID volume. Due to the distributed parity of the RAID system, a hard disk failure can be coped with without the volume completely failing.