In RAID 5 and RAID 6, what is the maximum number of failed disks allowed before data loss occurs?

In RAID 5, data is distributed across multiple disks with parity information, allowing for the recovery of data if one disk fails. Therefore, RAID 5 can tolerate the failure of one disk without any loss of data. This means that if more than one disk fails simultaneously, the data integrity is compromised and can lead to data loss.

On the other hand, RAID 6 builds upon the concept of RAID 5 by using two sets of parity data distributed across the disks. This additional layer of redundancy allows RAID 6 to handle the failure of up to two disks concurrently without resulting in data loss. As a result, RAID 6 provides a higher level of fault tolerance compared to RAID 5.

This distinction between the maximum allowable failed disks before losing data is what makes the correct choice highlight the specific tolerances of each RAID level. In summary, RAID 5 allows for one disk failure, while RAID 6 permits two disk failures before risking data loss.