Each computer system in operation today is certain to experience faults in its operational lifetime. There is more than one source, which can cause faults, for example environmental factors, communication, interaction with users, or hardware and software design flaws randomly build into the system. A reliable system is the one that would continue operation albeit in a degraded mode despite the presence of faults. In this paper, we introduce an efficient method to schedule a tandem of real-time tasks in cluster computing with possible processor failures. The method is based on developing an objective function that combines different scheduling goals. This objective function is used to guide the search algorithm to find an efficient solution. The proposed algorithm consists of three terms, reliability, deadline and tasks grouping to minimize remote communication among tasks. The proposed method creates a scheduling table based on the objective function then searches this table for a feasible solution. The method is efficient because it reduces communication between different tasks by grouping them together. This grouping process reduces application de-fragmentation as well.