RAID 6 is essentially an extension of RAID level 5 which allows for additional fault tolerance by using a second independent distributed parity scheme (dual parity)
Data is striped on a block level across a set of drives, just like in RAID 5, and a second set of parity is calculated and written across all the drives; RAID 6 provides for an extremely high data fault tolerance and can sustain multiple simultaneous drive failures
RAID 6 protects against multiple bad block failures while non-degraded
RAID 6 prodects against a single bad block failure while operating in a degraded mode
Perfect solution for mission critical applications
