利用集群技术实现Web服务器的负载均衡 集群和负载均衡的概念文库（Using cluster technology to implement the load balancing cluster and load balanced concept Library of Web server）.docVIP

利用集群技术实现Web服务器的负载均衡 集群和负载均衡的概念文库（Using cluster technology to implement the load balancing cluster and load balanced concept Library of Web server） Concepts of clustering and load balancing Cluster (Cluster) A cluster is a loosely coupled multiprocessor system consisting of an independent set of computer systems that communicate with each other over the network. The application can distribute messages via network shared memory to implement distributed computers. Load balancing (Load, Balance) Network load balancing is a dynamic balancing technology. It can analyze the data packets in real time through some tools, grasp the data flow status in the network, and distribute the tasks reasonably and evenly. This technique is based on existing network structure, provides a low-cost effective method to extend the bandwidth and throughput of servers, strengthen network data processing ability, improve the network flexibility and availability. Characteristic (1) high reliability (HA). Using cluster management software, when the main server fails, the backup server can automatically take over the work of the main server and switch over in time to achieve uninterrupted service to the user. (2) high performance computing (HP). That is, to make full use of the resources of each computer in the cluster and realize the parallel processing of complex operations, which are usually used in scientific computing fields, such as gene analysis, chemical analysis, etc.. (3) load balancing. That is, the load pressure is allocated to each computer in the cluster according to an algorithm to reduce the pressure of the main server and reduce the hardware and software requirements of the main server. Structure and characteristics of LVS system 1., Linux, Virtual, Server: LVS for short. Chinese is initiated by a Linux programmer Dr. Zhang Wensong and the leadership, solve the server cluster system based on Linux program, the goal is to create a good extensibility and high reliability, high perfo