Fault Tolerant VM Consolidation for Energy-Efficient Cloud Environments

Cloud computing applications are expected to guarantee the service performance which is determined by the Service Level Agreement (SLA) between cloud owner and client. While satisfying SLA, Virtual Machines (VMs) may be consolidated based on their utilization in order to balance the load or optimize energy efficiency of physical resources. Since, these physical resources are prone to system failure, any optimization approach should consider the probability of a failure on a physical resource and orchestrate the VMs over the physical plane accordingly. Otherwise, it is possible to experience unfavorable results such as numerous redundant application migrations and consolidations of VMs that may easily cause in SLA violations. In this paper, a novel approach is proposed to reduce energy consumption and number of application migration without violating SLA while considering the fault tolerance of the cloud system in the face of physical resource failures. Simulation results show that proposed model reduce energy consumption by approximately 37% and number of application migration by approximately 9%. Besides, in case of faults the increase of energy consumption is less than 11% when the proposed approach is used.