集群服务器系统前端接口子系统的设计与实现

基于链路聚集技术，提出并实现了一种适用于集群服务器系统的前端接口子系统方案，使得接口子系统中的接口机数目能随应用规模的变化而扩展，并增强了集群系统的可用性．链路聚集将多条物理链路聚合成一条单一虚拟的媒体访问控制（MAC）逻辑链路，通过将虚拟MAC解析为集群系统对外服务的虚拟IP（VIP），使多台接口机表现为单一IP的功能．利用链路聚集能在多条物理链路间进行负载均衡的功能，结合接口机的负载均衡策略来实现层次型的负载均衡，有效地提高了系统的I／O带宽．利用链路聚集的链路级容错，结合接口的检测机制实现了系统的高可用功能．理论分析和实验测试结果均表明，该方案能有效扩展集群系统的I／O带宽和处理能力．

Design and Implementation of Front End Subsystem in Cluster Server System

Based on link aggregation, a solution of the front end interface subsystem which is suited for cluster server system was provided and implemented; so as to expand the number of the front end nodes with changing of application scope and enhance the availability of the cluster system. Link aggregation can aggregate multiple physical links into a logical link with a single virtual MAC(media access control) address; and the function that multiple interface nodes representing as a single IP is achieved. Link aggregation can balance the network load in multiple physical links, which can be used to implement the hierarchical load balance with various load balance policies, and improve the I/O bandwidth of the system efficiently. In addition, with the link-level fault tolerance of link aggregation and the monitoring mechanism of the nodes the high availability of the system can be fulfilled. The results of both theoretical analysis and preliminary performance evaluation show that the solution expands the processing capability and I/O bandwidth of the cluster system.