Many companies today make use of a MySQL database as an integral part of their business operations. Yet, these same companies do not utilize a simple, but powerful feature of MySQL: database replication. We see clients avoiding the use of replication all too often, and it’s worth understanding that setting up MySQL replication isn’t all that complicated.
What makes MySQL replication different than other relational database systems? Simplicity. An out-of-box setup is mostly trivial, and should not be an overwhelming task for a junior database administrator, or even those otherwise unfamiliar with advanced MySQL tuning. There are several ways to begin configuring database replication when considering existing databases. One possible method begins by completing a database dump. The exported data will be imported on your planned MySQL slave server. Minor configuration changes must be made to your master and slave database servers, as well as some minor permission changes to allow replication. If binary logging was not enabled on your master database server, the master MySQL server must be restarted to enable the required components. The status of your replication partners can be checked at any time with some simple MySQL queries. Completing a similar configuration on other relational databases could take you hours of research and planning.
Why use MySQL replication in your organization? The most common reasons are backups (hot spare), performance, scalability, and high availability. MySQL replication in its most basic configuration consists of a master and a slave database server. The master server writes its transactional changes to a log. When a slave is configured, it sends requests to the master for a copy of the log. These changes are analyzed, then applied to the slave server. Once there is a slave database, you can then offload complex queries, searches or analytics that impact performance and stability of your production database. Databases can also be failed over to a slave server in a critical situation, or used to preserve the application’s deliverables to customers when experiencing downtime on the master server.
As we have experienced, many administrators of MySQL fear configuring replication a daunting task. In reality, it’s a simple approach that can provide many benefits to an organization’s applications. We have discussed some of the most common uses of MySQL replication, but MySQL replication also offers many advanced features as well.