This topic provides answers to frequently asked questions (FAQ) about data synchronization to AnalyticDB for MySQL V3.0 data sources.

What can I do if a PolarDB data source cannot be connected to?

  • Problem description: The connectivity test fails when you add a PolarDB data source.
  • Solution: Switch to the connection string mode and check the whitelist configuration of the PolarDB data source and the virtual private cloud (VPC) configuration of your exclusive resource group.

What can I do if an ApsaraDB for OceanBase data source cannot be connected to?

  • Problem description: The connectivity test fails when you add an ApsaraDB for OceanBase data source.
  • Solution: Switch to the connection string mode and check the whitelist configuration of the PolarDB data source and the virtual private cloud (VPC) configuration of your exclusive resource group.

What can I do if a MySQL data source cannot be connected to?

  • Problem description: The connectivity test fails when you add a MySQL data source.
  • Solution: Switch to the connection string mode and check the whitelist configuration of the PolarDB data source and the virtual private cloud (VPC) configuration of your exclusive resource group.

The system displays the following error message for a real-time synchronization node: com.alibaba.otter.canal.parse.exception.PositionNotFoundException: can't find start position for XXX. What can I do?

  • Problem description: The real-time synchronization node fails to run, and the system displays the error message com.alibaba.otter.canal.parse.exception.PositionNotFoundException: can't find start position for XXX.
  • Cause: The binary logging feature is disabled for the PolarDB data source.
  • Solution: Enable the binary logging feature for the PolarDB data source. For more information, see Configure data sources for data synchronization from PolarDB. In addition, you must change one or more data records and change the start time for running the real-time synchronization node to the current time.

The system displays the following error message for a real-time synchronization node: com.alibaba.otter.canal.parse.exception.CanalParseException: command : 'show master status' has an error! pls check. you need (at least one of) the SUPER,REPLICATION CLIENT privilege(s) for this operation. What can I do?

  • Problem description: The real-time synchronization node fails to run, and the system displays the error message com.alibaba.otter.canal.parse.exception.CanalParseException: command : 'show master status' has an error! pls check. you need (at least one of) the SUPER,REPLICATION CLIENT privilege(s) for this operation.
  • Cause: The account used to synchronize data is not authorized to access the PolarDB data source, or the connected PolarDB database is not deployed on the PolarDB Writer node.
  • Solution: Authorize the account to access the PolarDB data source. For more information, see Configure data sources for data synchronization from PolarDB. You can also check whether the connected PolarDB database is deployed on the PolarDB Writer node. When a real-time synchronization node is running, the system cannot capture data from the PolarDB Reader nodes of the PolarDB data source.

The system displays the following error message for a real-time synchronization node: com.alibaba.datax.plugin.reader.mysqlbinlogreader.MysqlBinlogReaderException: The mysql server does not enable the binlog write function. Please enable the mysql binlog write function first. What can I do?

  • Problem description: The real-time synchronization node fails to run, and the system displays the error message com.alibaba.datax.plugin.reader.mysqlbinlogreader.MysqlBinlogReaderException: The mysql server does not enable the binlog write function. Please enable the mysql binlog write function first.
  • Cause: The loose_polar_log_bin parameter is not specified for the PolarDB data source.
  • Solution: Specify the loose_polar_log_bin parameter. For more information, see Configure data sources for data synchronization from PolarDB.