| 摘要 |
A data processing method includes receiving data objects for storage by a primary storage device. A first instance of each of at least some of the received data objects is cached in a disaster-proof storage unit. A second instance of each received data object is sent for storage in a secondary storage device. A list of identifiers of the data objects that are cached in the disaster-proof storage unit at a given point in time is sent from the disaster-proof storage unit to the secondary storage device. Following an event that renders at least some of the data objects on the primary storage device inaccessible, a request sent to the secondary storage device to access a given data object is received. A selection is made, responsively to the list, to serve the cached first instance or the stored second instance of the given data object in response to the request. |
