关键词: 分布式数据库, 高可用性, Raft一致性协议, 日志同步

Abstract: With the rapid development of Internet and the upcoming Big Data era, the limitation of traditional database has been emerged and enlarged. The distributed database system based on massive data storage and high concurrent accesses has become more and more popular. Alibaba group developed a distributed database system suitable for mass data storage named OceanBase, which supports two deployment modes, i.e.〖KG-*3〗, single cluster and multiple clusters. But the availability of multiple clusters mode is not efficient and can’t satisfy the requirement of some critical applications, where it does not support the automatic switch between master cluster and slave cluster when a failure occurred and the inconsistent log is also generated during switching under multiple clusters mode. To address these problems, we analysis the high availability solutions of the traditional database,aiming at the characteristics of OceanBase architecture, combining the idea of in Raft, and then designs and implements the distributed election module based on the timestamp of logs, the automatic clusters switching module and the strong synchronization logs module based on QUORUM.The experimental results showed that the above approachescould improve the availability of the whole system.