To use outbound replication from HeatWave Service, the replica and its network connection to the DB system source need this configuration.

• Your VCN and local network must be configured to permit replication traffic between the DB system source and the replica. You can use VPN Connect, FastConnect, or OpenVPN Access Server for the connection.
• The replica must be the same version as, or a higher version of MySQL than, the DB system source.
• The replica must use GTIDs, with the system variable GTID_MODE set to ON. This is not the default in MySQL server, but it is the default in HeatWave Service. Binary log file position based replication is not supported by HeatWave Service, only GTID-based replication. See MySQL Reference Manual - gtid_mode.
• The replica must use the system variable enforce-gtid-consistency. See enforce_gtid_consistency.
• The replica must use the system variable partial-revokes=ON. See partial_revokes.
• The DB system source and the replica must run with the same lower_case_table_names system variable value. See Initialization Variables.
• The server_id system variable value must be defined on the replica and be unique in your replication topology. The server_uuid system variable value must also be unique. See server_id and server_uuid.
• The replica must contain the same timezone definitions as the DB system source. The default timezone of HeatWave Service is UTC. See Populating the Timezone Tables.
• Outbound replication from a DB system source to an external replica, or to another DB system as the replica, requires you to create a dump of the DB system source using MySQL Shell's dumpInstance utility and import that dump on the replica, including users, before starting replication. See Overview of Exporting and Importing.
• Users on the DB system source must be present on the replica. Partial revokes requires that the roles and users creating grants are present on the replica. The users on the source are exported as part of the MySQL Shell dump and must be imported to the replica.
  Note
  
  

  The user account used to load the MySQL Shell dump on the replica must have the necessary privileges to load users and data.

The replica must be able to apply the transactions from the DB system source before the source's binary log is purged. The default value of binlog_expire_logs_seconds is 3600 seconds (1 hour). If your replica will need more time than this to apply the transactions, create a new HeatWave Service configuration with the required expiration value, and create a new source DB system using the new configuration.

The replication user must be present on the DB system source server with the required privileges. See Creating a Replication User On a Source Server for the steps to set up the replication user.