In this paper, a cyber-attack tolerant control strategy for embedded controllers in a cyber-physical system is presented. A dual redundant control architecture that combines two identical controllers that are switched periodically between active and restart modes is proposed. The strategy is addressed to mitigate the impact due to corruption of the controller software by an adversary. We analyze the impact of the resetting and restarting the controller software and performance of switching process. The minimum requirements in the control design, for effective mitigation of cyber-attacks to the control software, that implies a "fast" switching period is provided. The simulation results demonstrate the effectiveness of the proposed strategy when the time to fully reset and restart the controller is faster than the time taken by adversary to compromise the controller. The results also provide insights into the stability and safety regions and the factors that determine the effectiveness of the proposed strategy.