A Differential Approach for Configuration Fault Localization in Cloud Environments

Configuration fault localization is the process of identifying fault in the configuration of component(s) that is the source of failure given a set of observed failure conditions. Configuration faults are harder to detect than on/off failures as it involves analysis of the parameters that constitute the configuration. While distributed systems become more complex and interconnected, the requirements on configuration fault localization have changed. In this paper we present a new, simple but effective approach to configuration fault localization, which utilizes the difference in configuration parameters of components that share a resource. We establish a Reference Configuration State (RCS) by determining a set of non-faulty probing components for each faulty component with respect to shared resources. Performing difference in configuration of reference state with that of the faulty components localizes faulty configuration parameter. Experiments through simulations demonstrate that our approach is effective in identifying configuration faults with reduced time and increased accuracy. Our algorithm gracefully handles the complexity of the problem as the system size grows.