A scalable architecture for clustered network attached storage

Network attached storage systems must provide highly available access to data while maintaining high performance, easy management, and maximum scalability. In this paper we describe a clustered storage system that was designed with these goals in mind. The system provides a unified file system image across multiple nodes, which allows for simplified management of the system. Availability is preserved with multiple nodes and parity-striped data across these nodes. This architecture provides two key contributions: the ability to use low-cost components to deliver scalable performance and the flexibility to specify redundancy and performance policy management on a file-by-file basis. The file system is also tightly integrated with standard distributed file system protocols thereby allowing it to be used in existing networks without modifying clients.