Due to its synchronous nature, Galera performance can be limited by the slowest node in the cluster. So running heavy reporting queries or making frequent backups on one node, or putting a node across a slow WAN link to a remote data center might indirectly affect cluster performance. Combining Galera and asynchronous MySQL replication in the same setup, aka Hybrid Replication, can help. A slave is loosely coupled to the cluster, and will be able to handle a heavy load without affecting the performance of the cluster. The slave can also be a live copy of the Galera cluster for disaster recovery purposes.
We had explained the different steps to set this up in a previous post. With ClusterControl 1.2.9 …
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