在线学习系统的数据库高可用性研究

Application Research of High Availability for database of Online Learning System

文章通过Linux HA组件与DB2 HADR（High Availability and Disaster Recovery）组件相结合的方式实现在线教学系统的数据库高可用性方案。首先介绍了HADR实现DB2的双机热备，并分析了HADR自身存在的无法自动切换问题，然后提出了结合HA和HADR实现DB2数据库自动切换的解决方案，并对方案中出现的特别问题提出了解决办法，为提高在线学习系统的可用性提供了数据库保证。

A new solution of high availability for database of OLS（Online Learning System）was issued in this paper and its main idea is to combine Linus HA and DB2 HADR to resolve the problem that HADR cannot failover automatically. Firstly， the basic theory of HADR was introduced and the problem mentioned above was explained， then the solution was suggested to offer a high availability DB2 Database service. At last， the experiment was processed and some crucial problems in the process were described. The solution monitored the status of both servers at instance， so it is a much deeper strategy of high availability for DB2. This will ensure the high availability of the OLS.