The increasing complexity of real-time systems has lead to the adaptation of component based methods for their development which has a promising potential for faster and more cost effective development of complex real-time systems by facilitating reuse of the real-time components. This is enabled by the components' composition using contracts, which ensures 'correctness by construction'. Modern real-time systems typically consist of mixed criticality components, and scheduling them in a fault-tolerant as well as efficient way, on a distributed platform, is a challenging task. In this paper, we propose a contract-based approach to fault tolerant scheduling of mixed criticality real-time components on a distributed platform, by providing guarantees for the hard real-time components through offline negotiated contracts, as well as flexibility for the soft real-time components through online (re-)negotiated contracts. The proposed approach uses optimization techniques, that uses timing requirements and the recommendations of studies like Fault Hazard Analysis and Zonal Analysis, to provide the contractual parameters for the mixed-criticality components.