Costs and limitations of device parity protection

Here are the costs and limitations of device parity protection:

RAID 5

The system is only capable of handling one disk-unit failure. If more than one disk unit fails, the system may also fail depending on the ASP configuration.

RAID 6

The system is capable of handling up to two disk-unit failures. However, because the amount of parity data is twice as much as parity data in RAID 5, the available storage for user data is reduced. If more than two disk units fail, the system may also fail depending on the ASP configuration.