In this paper, the authors have discussed about various fault tolerant task scheduling algorithm for multi core system based on hardware and software. Hardware based algorithm which is blend of triple modulo redundancy and double modulo redundancy, in which AVF is considered while deciding the scheduling other than EDF and LLF scheduling algorithms. In most of the real-time system the dominant part is shared memory. Low overhead software based fault tolerance approach can be implemented at user-space level so that it does not require any changes at application level.