In the previous chapters, we saw solutions such as slave / multislave / master replications, slave with cluster, and load balancers, but there were no solutions that could provide several write replications. This is where Galera Cluster comes into the picture, bringing that and other features that will be discussed in detail in this chapter.

Galera Cluster is a synchronous multimaster solution created by Codership. It's a patch for MySQL and MariaDB with its own commands and configuration. On MariaDB, it has been officially promoted as the MariaDB Cluster.

Galera Cluster provides certification-based replication. This means that each node certifies the replicated write set against other write sets. You don't have to worry about data integrity, as it manages it automatically and very well. Galera Cluster is a young product, but is ready for production.

If you have already heard of MySQL Cluster, don't be confused; this is not the same thing...