This topic describes how to synchronize data from a self-managed MySQL database to a Message Queue for Apache Kafka instance by using Data Transmission Service (DTS). The data synchronization feature allows you to extend message processing capabilities.

Prerequisites

  • The version of the self-managed MySQL database is 5.1, 5.5, 5.6, 5.7, or 8.0.
  • The version of the destination Message Queue for Apache Kafka instance is 0.10.1.0 to 2.x.
  • In the destination Message Queue for Apache Kafka instance, a topic is created to receive the synchronized data. For more information, see Create a topic.

Background information

Message Queue for Apache Kafka is a distributed, high-throughput, and scalable message queue service that is provided by Alibaba Cloud. It provides fully managed services for the open source Apache Kafka to resolve the long-standing shortcomings of open source products. Message Queue for Apache Kafka allows you to focus on business development without spending much time in deployment and O&M. Message Queue for Apache Kafka is used in big data scenarios such as log collection, monitoring data aggregation, streaming data processing, and online and offline analysis. It is important for the big data ecosystem.

Precautions

  • DTS uses read and write resources of the source and destination databases during initial full data synchronization. This may increase the loads of the database servers. If the database performance is unfavorable, the specification is low, or the data volume is large, database services may become unavailable. For example, DTS occupies a large amount of read and write resources in the following cases: a large number of slow SQL queries are performed on the source database, the tables have no primary keys, or a deadlock occurs in the destination database. Before you synchronize data, evaluate the impact of data synchronization on the performance of the source and destination databases. We recommend that you synchronize data during off-peak hours. For example, you can synchronize data when the CPU utilization of the source and destination databases is less than 30%.
  • The source database must have PRIMARY KEY or UNIQUE constraints and all fields must be unique. Otherwise, the destination database may contain duplicate data records.

Limits

  • Only tables can be selected as the objects to synchronize.
  • DTS does not synchronize the data in a renamed table to the destination Kafka cluster. This applies if the new table name is not included in the objects to synchronize. If you want to synchronize the data in a renamed table to the destination Kafka cluster, you must reselect the objects to be synchronized. For more information, see Add an object to a data synchronization task.

Before you begin

Create an account for a user-created MySQL database and configure binary logging

Procedure

  1. Purchase a data synchronization instance. For more information, see Purchase a DTS instance.
    Note On the buy page, set Source Instance to MySQL, set Dstination Instance to Kafka, and set Synchronization Topology to One-way Synchronization.
  2. Log on to the DTS console.
  3. In the left-side navigation pane, click Data Synchronization.
  4. At the top of the Synchronization Tasks page, select the region where the destination instance resides.
  5. Find the data synchronization instance and click Configure Synchronization Channel in the Actions column.
  6. Configure the source and destination instances.
    Configure the source and destination instances
    Section Parameter Description
    None Synchronization Task Name DTS automatically generates a task name. We recommend that you specify an informative name to identify the task. You do not need to use a unique task name.
    Source Instance Details Instance Type Select an instance type based on the deployment of the source database. In this example, select User-Created Database in ECS Instance. You can also follow the procedure to configure data synchronization tasks for other types of self-managed MySQL databases.
    Instance Region The source region that you selected on the buy page. You cannot change the value of this parameter.
    ECS Instance ID Select the ID of the Elastic Compute Service (ECS) instance that hosts the self-managed MySQL database.
    Database Type This parameter is set to MySQL and cannot be changed.
    Port Number Enter the service port number of the self-managed MySQL database.
    Database Account Enter the account of the self-managed MySQL database. The account must have the SELECT permission on the required objects, the REPLICATION CLIENT permission, the REPLICATION SLAVE permission, and the SHOW VIEW permission.
    Database Password Enter the password of the database account.
    Destination Instance Details Instance Type Select User-Created Database Connected over Express Connect, VPN Gateway, or Smart Access Gateway.
    Note You cannot select Message Queue for Apache Kafka as the instance type. You can use Message Queue for Apache Kafka as a self-managed Kafka database to configure data synchronization.
    Instance Region The destination region that you selected on the buy page. You cannot change the value of this parameter.
    Peer VPC Select the ID of the virtual private cloud (VPC) to which the destination Message Queue for Apache Kafka instance belongs. To obtain the VPC ID, you can log on to the Message Queue for Apache Kafka console and go to the Instance Details page of the Message Queue for Apache Kafka instance. In the Basic Information section, you can view the VPC ID.
    Database Type Select Kafka.
    IP Address Enter an IP address that is included in the Default Endpoint parameter of the Message Queue for Apache Kafka instance.
    Note To obtain an IP address, you can log on to the Message Queue for Apache Kafka console and go to the Instance Details page of the Message Queue for Apache Kafka instance. In the Basic Information section, you can obtain an IP address from the Default Endpoint parameter.
    Port Number Enter the service port number of the Message Queue for Apache Kafka instance. The default port number is 9092.
    Database Account Enter the username that is used to log on to the Message Queue for Apache Kafka instance.
    Note If the instance type of the Message Queue for Apache Kafka instance is VPC Instance, you do not need to specify the database account or database password.
    Database Password Enter the password of the username.
    Topic Click Get Topic List and select a topic name from the drop-down list.
    Kafka Version Select the version of the Message Queue for Apache Kafka instance.
    Encryption Select Non-encrypted or SCRAM-SHA-256 based on your business and security requirements.
  7. In the lower-right corner of the page, click Set Whitelist and Next.
    Note
    • You do not need to modify the security settings for ApsaraDB instances (such as ApsaraDB RDS for MySQL and ApsaraDB for MongoDB) and ECS-hosted databases. DTS automatically adds the CIDR blocks of DTS servers to the whitelists of ApsaraDB instances or the security group rules of Elastic Compute Service (ECS) instances. For more information, see Add the CIDR blocks of DTS servers to the security settings of on-premises databases.
    • After data synchronization is complete, we recommend that you remove the CIDR blocks of DTS servers from the whitelists or security groups.
  8. Select the objects to synchronize.
    Select the objects to synchronize
    Parameter Description
    Data Format in Kafka The data that is synchronized to the Kafka cluster is stored in the Avro or Canal JSON format. For more information, see Data formats of a Kafka cluster.
    Policy for Shipping Data to Kafka Partitions The policy used to synchronize data to Kafka partitions. Select a policy based on your business requirements. For more information, see Specify the policy for synchronizing data to Kafka partitions.
    Select the objects to synchronize Select one or more tables from the Available section and click the Rightwards arrow icon to add the tables to the Selected section.
    Note DTS maps the table names to the topic name that you select in Step 6. If you want to rename the topic, you can use the object name mapping feature. For more information, see Rename an object to be synchronized.
    Rename Databases and Tables

    You can use the object name mapping feature to rename the objects that are synchronized to the destination instance. For more information, see Object name mapping.

    Retry Time for Failed Connections
    By default, if DTS fails to connect to the source or destination database, DTS retries within the next 720 minutes (12 hours). You can specify the retry time based on your needs. If DTS reconnects to the source and destination databases within the specified time, DTS resumes the data synchronization task. Otherwise, the data synchronization task fails.
    Note When DTS retries a connection, you are charged for the DTS instance. We recommend that you specify the retry time based on your business needs. You can also release the DTS instance at your earliest opportunity after the source and destination instances are released.
  9. In the lower-right corner of the page, click Next.
  10. Configure initial synchronization.
    Kafka: Configure initial synchronization
    Setting Description
    Initial Synchronization Select both Initial Schema Synchronization and Initial Full Data Synchronization. DTS synchronizes the schemas and historical data of the required objects and then synchronizes incremental data.
    Filter options Ignore DDL in incremental synchronization phase is selected by default. In this case, DTS does not synchronize DDL operations that are performed on the source database during incremental data synchronization.
  11. In the lower-right corner of the page, click Precheck.
    Note
    • Before you can start the data synchronization task, DTS performs a precheck. You can start the data synchronization task only after the task passes the precheck.
    • If the task fails to pass the precheck, you can click the Info icon icon next to each failed item to view details.
      • You can troubleshoot the issues based on the causes and run a precheck again.
      • If you do not need to troubleshoot the issues, you can ignore failed items and run a precheck again.
  12. Close the Precheck dialog box after the following message is displayed: Precheck Passed. Then, the data synchronization task starts.
    You can view the state of the data synchronization task on the Synchronization Tasks page. View the state of a data synchronization task