Cyberspace mimic domain name system (CMDNS) adopts dynamic heterogeneous redundant architecture with strategic decision mechanism to control the effectiveness of uncertain disturbance. There is lack of methods to evaluate the availability and awareness security of CMDNS. To further describe and analyze the characteristics of CMDNS accurately, the Generalized stochastic Petri net (GSPN) is used to model the attack disturbance and defense of mimic Domain name system (DNS), and the availability and awareness security of Dissimilar redundancy system (DRS) and mimic DNS under different disturbance intensities are compared. We compared the different effect of local service query and real network query on the average response delay. The results show that the introduction of mimic architecture will inevitably pay the corresponding delay cost which increase 9.3％ compared with traditional local DNS, but it has little effect on the service which only increases by 1.9％ compared with the DNS transmission delay at the network communication level.