A backup entity and a method for backing up a disk volume of a production device are provided. The backup entity is configured to: create a first backup image of the disk volume, in a backup repository. Further, the backup entity is configured to obtain a first indication from the production device, wherein the first indication is indicative of a first operation to be performed by the production device on the disk volume. The backup entity is further configured to perform the first operation on the first backup image, to obtain a second backup image in the backup repository. According to the application, a solution to mimic an operation that changes data of a production storage, in a backup system, is provided, which can reduce the amount of data sent from the production storage to the backup system and thus reduce a backup window.