Distant Disaster-tolerant And Backup System Based On IP-SAN

Data is becoming a more and more import strategic resource. Any damage, loss of business data or interruption of client service would lead to great loss to the whole industry or department. With the development of network, distributed data storage has emerged as an effective method to deal with possible data catastrophe. To ensure integrity, security of business data and continuity of services, building off site data backup system is now an urgent task.The thesis studies the requirement of today's enterprises, investigated the principles of Disaster-tolerant and Backup System thoroughly and compared popular network storage patterns: DAS, NAS, SAN and IP-SAN, and then designed an off-the-site disaster-tolerant and backup system. The system utilizes the advantages of IP-SAN, which has high-speed, fault-tolerant for single cell and can be quickly scaled and conveniently managed. The system is also compatible to many different networks with elegant infrastructure and fully exploits the existing Ethernet for long distance off-the-site backup.Then the thesis studies the key technologies used in the system. A distant mirror backup subsystem is designed based on IP-SAN which supports distant data backup. The system runs on Linux kernel, which supports all the file systems and storage devices on Linux transparently to higher layer applications and introduces an improved computing abstract algorithm NSC. Through experiment, the main functions and performance is tested, validating that the distant mirror backup subsystem can submit the updated local data to remote mirror system in real-time and it has little impact to the local system's performance.A improved abstracting algorithm NSC and package transmitting method without 3-way hand-shaking facility is introduced during the designing of this system, which effectively improve the performance of data backup and consistence checking, lowering the network payload and system reliability and responsibility. Experiments show that the improved NSC algorithm and the proposed datagram transmit protocol effectively improves the data backup and consistence validating speed with lower network payload, with improved reliability and response speed. It's demonstrated as a low cost and plausible designing scheme.