A distributed storage server includes a plurality of data server devices and a plurality of metadata server devices. The metadata server devices store metadata associated with data which is distributively stored in the data server devices. A selected metadata server device checks whether a dangling directory occurs by performing a rename operation, based on information associated with a full path of a parent directory of a source and a full path of a parent directory of a target included in a request of the rename operation. When it is determined that the dangling directory does not occur, the selected metadata server device processes transactions directed to the metadata such that the rename operation is performed. The checking whether the dangling directory occurs is performed before a transaction period for processing the transactions.