A data storage system comprises data storage module for storing failure data when message is processed, back-up data storage module for storing failure data when failure data is stored into data storage module, data processing module for connecting back-up data storage module to data storage module in order to store storage-failure data into back-up data storage module when data is failed to be stored into data storage module and restore data in back-up data storage module into data storage module when normal storage service of data storage module is restored. |