High Performance MySQL, 4th Edition

Chapter 9. Replication

MySQL’s built-in replication is the foundation for building large, high-performance applications on top of MySQL, using the so-called “scale-out” architecture. Replication lets you configure one or more servers as replicas of another server, keeping their data synchronized with the source copy. This is not just useful for high-performance applications—it is also the cornerstone of many strategies for high availability, scalability, disaster recovery, backups, analysis, data warehousing, and numerous other tasks.

In this chapter, our focus is less on what each feature is and more on when to use it. The official MySQL documentation is exceptionally detailed at explaining what features like semisynchronous replication, multisource replication, and so on are, and you should refer to this documentation when setting up these features.

A Note on Terminology

Long-time users of MySQL will be familiar with the terminology master and slave as it relates to replication. These terms have since been replaced with source and replica. This book attempts to maintain the new wording to align with this change. Some older versions of MySQL still contain those replaced terms, so refer to the MySQL manual as needed.

Replication Overview

The basic problem replication solves is keeping data synchronized among database instances within the same topology. It does this by writing events that modify data or data structure to a log on a source server. Replica servers can then read ...