This study applies N-policy to an M X /G/1 repairable machining system with Bernoulli feedback and general setup time. The arrival rate of the failed units depends on the state of the system which may be in buildup, setup and busy states. Supplementary variable technique is employed to obtain the probability generating function for the system queue size distribution and the mean number of failed units in the system under steady state conditions. The Laplace-Stieltjes transform of the waiting time is obtained which is further used to evaluate its mean value. The total operational cost of the system is minimized in order to determine the optimal value of N.