In the substation SCADA system

it should be ensured that there will be neither up nor down data reports lost during the dual-server switching process

and that the information of real-time database and historical database should be synchronized automatically when the dual-server comes back to normal. In the dual network architecture of the substation SCADA system

how to make the system work correctly is also a problem when the dual-server's networks fail alternately. An undisturbed switching algorithm of dual-server for the substation SCADA system is introduced to ensure that network data and historical record will not get lost at the moment of the dual-server switching. This paper focuses on the server switching process

the problem in either respect of the dual-server being the system operation with a disconnected network and the synchronization of real-time database and historical database.