A computer-implemented method performed while performing a data migration from a source storage system to a destination storage system ; the method comprising performing an initial synchronization , at least one intermediate incremental synchronization , and a final cutover synchronization of data items; and wherein the initial synchronization comprises: - scanning the source and destination storage system thereby obtaining an initial source and destination data item list ; - generating commands for performing the initial synchronization based on the scanning; - executing the commands; - obtaining results of the executed commands; and - creating and storing status records of the respective data items indicative for the synchronization state of the respective data items based on the results; and wherein each of the at least one intermediate incremental synchronizations and the final cutover synchronization comprises: - scanning the source and destination storage system thereby obtaining the source and destination data item list ; - retrieving the stored status records of the respective data items indicative for the last known synchronization state of the respective data items; - generating commands for performing the intermediate incremental synchronization based on the source and destination data item list and the status records ; - executing the commands ; - obtaining results of the executed commands as a result list ; - determining , from the result list, a merge list comprising updates for the status records ; and - updating the status records based on the merge list; and wherein during the final cutover synchronization all access to the data is denied or only read-only access is granted. - scanning the source and destination storage system thereby obtaining an initial source and destination data item list ; - generating commands for performing the initial synchronization based on the scanning; - executing the commands; - obtaining results of the executed commands; and - creating and storing status records of the respective data items indicative for the synchronization state of the respective data items based on the results; and wherein each of the at least one intermediate incremental synchronizations and the final cutover synchronization comprises: - scanning the source and destination storage system thereby obtaining the source and destination data item list ; - retrieving the stored status records of the respective data items indicative for the last known synchronization state of the respective data items; - generating commands for performing the intermediate incremental synchronization based on the source and destination data item list and the status records ; - executing the commands ; - obtaining results of the executed commands as a result list ; - determining , from the result list, a merge list comprising updates for the status records ; and - updating the status records based on the merge list; - scanning the source and destination storage system thereby obtaining the source and destination data item list ; - retrieving the stored status records of the respective data items indicative for the last known synchronization state of the respective data items; - generating commands for performing the intermediate incremental synchronization based on the source and destination data item list and the status records ; - executing the commands ; - obtaining results of the executed commands as a result list ; - determining , from the result list, a merge list comprising updates for the status records ; and - updating the status records based on the merge list; and wherein during the final cutover synchronization all access to the data is denied or only read-only access is granted. <EOS>