Supporting Cluster-Based Network Services on Functionally Symmetric Software Architecture

Server and storage clustering has become a popular platform for hosting large-scale online services. Elements of the service clustering support are often constructed using centralized or hierarchical architectures, in order to meet performance and policy objectives desired by online applications. For instance, a central Executive node can be employed to make efficient resource management decisions based on a complete view of cluster-wide resource availability as well as request demands. Functionality symmetric software architecture can enhance the robustness of cluster-based network services due to its inherent absence of vulnerability points. However, such a design must satisfy performance requirements and policy objectives desired by online services. This paper argues for the improved robustness of functionally symmetric architectures and presents the designs of two specific clustering support elements: energy-conserving server consolidation and service availability management. Our emulation and experimentation on a 117-server cluster show that the proposed designs do not significantly compromise the system performance and policy objectives compared with the centralized approaches.