Design And Implementation Of Network Environment Host Failure Detection System Based On Fault Tree

With the rapid development of network technique, Internet system is increasingly complex and large. System fault detection and network environment host is a crucial factor to ensure network security. Therefore fault detection and diagnosis system in computer system should be built, which can scientifically manage all the faults in the network, record the causes and relative information of each fault and finally identify and correct the network environment host faults as well as guarantee system can provide a reliable serviceAs a rational analysis tool of fault detection and diagnosis, fault tree model describes the internal relations and logical relations of system. Furthermore, the model has many advantages, such as intuition, simpleness, and so on. The fault tree is similar to the thinking method of human being, which is easily understandable, usually applied in practice and easily used in combination with other methods, and is an advantaged tool for the fault diagnosis of large-scale and complicated systems.Based on fault detection and diagnosis, this thesis makes an intensive study of the application of fault tree in fault detection and diagnosis technology and also designs a fault detection system.Firstly, this thesis introduces the deficiency of the present network environment host fault management and the necessity of the development of fault detection system. On the basis of the analysis of fault diction methods based on fault tree and the traditional fault tree analysis methods, the concept of least partition and important degree are introduced into the analysis of fault tree. During the course of fault tree analysis, the probability of each fault to occur is quantitatively calculated by using the least partition, and at the same time the test cycle of fault detection and diagnosis system is qualitatively analyzed according to the fault important degree. Secondly, this thesis defines the specific framework, module division and process design of host monitoring in fault detection system based on the model of fault tree. Thirdly, this thesis realizes host monitoring in fault detection and diagnosis system. And we offer the function and performance test on the system detected, and perform the valuation on the test results.The system realized in this thesis can effectively detect the running station of system by extracting host feature sequence which includes utilization of center processing unit, utilization of MEM, speed of I/O and flow rate of network card. As a means of the collection and analysis, host agent adopted in the system can greatly save the bandwidth of network transmission. In addition, by processing faults automatically, this system effectively reduces the fault processing time and simultaneously alleviates the workload of maintain engineers.