Design Of Dual CPU Redundant Backup System Based On CPCI

In recent years, the defense cutting-edge domains such as aerospace, Marine andindustrial applications put forward higher and higher requirements on the reliabilityand real-time performance. In some critical, high-performance and complexapplications need to ensure the system can stable error-free work, and any small faultwill cause immeasurable loss. Although high-reliability components can be used toimprove the stability of the system, but still cannot meet the requirements. By usingthe redundancy backup technology is an effective way to solve this problem. DualCPU redundancy technique is commonly used to improve the reliability of the system,in various fields has been used. This article relies on related research projects to studythe redundant fault-tolerant technology and design the dual CPU redundancy backupsystem. The main work is as follows:(1) Studied the High Availability concepts and models. Researched the concept,the basic form and the basic process of redundant fault-tolerant technology, analyzedthe key technology of redundant fault-tolerant, and evaluated the reliability of thetechnology. Analyzed the advantages and disadvantages of the third-party arbitrationredundancy mode, cold standby redundancy mode and hot backup redundancy modein dual CPU redundant backup technology as well as the differences between the dualCPU mutual redundant backup technology and dual CPU master slave backuptechnology.(2) For practical applications, designed a dual CPU redundant backup systembased on CPCI bus and the VxWorks real-time operating system. In a CPCI industrialchassis has realized mutual redundant backup system between two pieces of CPUcard. The system can real-time monitor the CPU，when the master CPU failure thebackup CPU can automatically switch within10ms and replace the master CPU. Atthe same time, the failure CPU can be self-troubleshooting or artificial replacement.The system through two pieces of CAN card to communicate with the rest of PC and constitute a star network. All the cards support hot-swap, all data real time backupthrough the fiber reflective memory card.(3) Transformed the original chassis, since the original chassis supports only asingle CPU card, the dual CPU redundancy backup cannot be achieved. So wedesigned a system extension card to achieve the support of dual CPU; designed theCPCI bus switching mechanism to realize the real time CPU card switch withoutdisturbance; designed the CPLD arbitration module to achieve a real time faultmonitoring and automatic switching logic; achieved the communication with the restof PC through CAN card; designed the dynamic loading driver since the CAN cardneeds to support hot-swap; implemented a heartbeat packet sent; Completed theoverall application design.The dual CPU redundant backup system designed in this paper has realized theredundancy backup function between the two CPU, under the premise to meetreal-time requirements, effectively improve the reliability of the system.