Differences between MySQL semi-sync and MySQL sync

MySQL sync and MySQL semi-sync DBMSs are available in Managed Databases. The table below shows the differences between them.

	MySQL replication	MySQL semi-synchronous replication
Replication	Multi-master (synchronous) — requires all replicas to receive data for a write to be confirmed	Master-replica (semi-synchronous) — requires at least one of the replicas to receive data for a write to be confirmed
Fault tolerance	You can create a cluster without replicas or with only two replicas	You can create a cluster without replicas, with one, or with two replicas
Limitations	Fault-tolerant clusters with replicas are subject to limitations	No limitations
Connecting to the cluster	Port 6033 is used to connect to ProxySQL	Port 3306 is used to connect to the cluster