This application will allow you to calculate:

- The actual computing capacity per disk

- The number of groups reconnandés in RAID 5, RAID 6 and RAID 10

- Gross capacity as your data
- The payload
- The number of discs HotSpare
- The number of data disks
- The number of disk mirror
- The average number of groups or fractions thereof.
etc. ....

Level 0: called striping

RAID-0, called striping (interleaving or translate Striped sometimes unfairly called stripping) is to store the data and distribute them across all disks in the cluster. In this way, there is no redundancy, we can not talk about fault tolerance. Indeed in case of failure of one disk, the entire distributed data on the disks will be lost.


Level 1: called mirroring, shadowing or duplexing

RAID 1 is designed to duplicate the information stored on multiple disks, we are talking thus mirroring or shadowing to describe this process.

Level 5: called disk array with block-interleaved distributed parity

Level 5 is similar to level 4, that is to say that parity is calculated at the sector level, but distributed across all disks in the cluster.


Level 6: called disk array with block-interleaved distributed parity

Level 6 has been added to the levels defined by Berkeley. It defines the use of 2 parity functions, and then stored on two disks dedicated. This level allows for redundancy in case of damage to both drives simultaneously. That means at least 4 disks to implement RAID-6.