Some disaster may result in the simultaneous collapse of multiple data disks on the data center storage system. If a mirror backup was used, it would be highly likely that the data cannot be recovered. But if the redundancy technology, based on the odd parity, is used, and it has been ensured that all disks have equal probability of operation, then not only can the technology recover the data of one or two collapsed data disks, but it can also recover the data of three or more simultaneously collapsed data disks.