Study And Design On Two-node Hot-standby Cluster

Along with the popularization of enterprise information system and the development of Electronic Commerce, the operation of modern enterprise depends on the information technology increasingly. The pivotal data in the computer system is increasing at very fast speed, lose of the data may cause serious hurt to enterprise. So enterprise requires higher availability of the data. Because just a shortly shutdown may cause service fail and economic expense. Therefore, high availability and dependability of computer system is an important research field of computer recently.The purpose of this paper is to research of cluster high availability system. Research analyzing causes of system failures shows hardware has always been the most common reason. The key to solve hardware failures is cluster. To get high availability, adopting redundancy components,system backup,detection and recovery method, is cluster operating system's necessary function. We give the definition and the art of state of research of high availability, then propose the availability analysis method and calculate formula.First, We analysis the availability of two node system and research on reality of it, then we describe two nodes' high availability system software architecture,hardware architecture,application state conversion and key problem. Base on the characteristic of the system ,we bring forward two ways to increase system's availability: firstly consider single points of failure,database and service failover,reliability of"heartbeat"signal,network etc. add the lowest cost to farthest reduce the probability of failures,cut down the time of maintain, in order to increase the availability of two node system, exercise Markov process to analyze the availability, found the frame of dependability and mathematic model, quantitative analysis the availability of the improved system. Secondly through research the source file and configuration file we point out the shortcoming of heartbeat protocol, then give improved method ,mostly enhance the function of monitor, increase the facility and agility of administrators.