Virtualization and Fault Tolerance in Cloud Computing

Abstract

Fault tolerance in cloud computing is a grand challenge problem now a days. The main fault tolerance issues in cloud computing are detection and recovery. To combat with these problems, many fault tolerance techniques have been designed to reduce the faults. In this research work,a Virtualization and Fault Tolerance (VFT) technique is used to reduce the service time and to increase the system availability. A Cloud Manager (CM) module and a Decision Maker (DM) are used in this scheme to manage the virtualization, load balancing and to handle the faults. In the first step virtualization and load balancing are done and in the second step fault tolerance is achieved by redundancy, checkpointing and fault handler.The main load balancing issues in cloud computing is load calculation and load distribution. To solve these issues, many load balancing techniques have been designed to distribute tasks properly. In this work, a Load Balancing Technique for Virtualization and Fault Tolerance in Cloud Computing (LBVFT) is applied to assign the tasks to the virtual nodes.LBVFT is mainly designed to assign tasks to the virtual nodes depending on the success rates (SR) and the previous load history. In our load assigning technique assignment is done by the load balancer (LB) of cloud manager (CM) module in the basis of higher success rate and lower load of the available nodes.A Randomized Searching Algorithm is designed to select a virtual node.Performance of the Randomized Searching Algorithm lies between Binary Search and Linear Search Algorithms. VFT is mainly designed to provide reactive as well as proactive fault tolerance. In this approach a fault handler is included in the virtualization part. Fault handler blocks the unrecoverable faulty nodes along with their virtual nodes for future requests and removes the temporary software faults from the recoverable faulty nodes and makes them available for the future requests.