ApsaraDB for MyBase:Migrate data from an ApsaraDB MyBase for MySQL instance to an ApsaraDB RDS for MySQL instance

Prerequisites

• An ApsaraDB MyBase for MySQL instance is created. For more information, see Create an ApsaraDB MyBase for MySQL instance.

• An ApsaraDB RDS for MySQL instance is created. For more information, see Create an ApsaraDB RDS for MySQL instance.

• The available storage space of the ApsaraDB RDS for MySQL instance is larger than the total size of the data in the ApsaraDB MyBase for MySQL instance.

Limits

Billing rules

Migration types

• Schema migration

  Data Transmission Service (DTS) migrates the schemas of objects from the source database to the destination database.

  Note

  • DTS supports schema migration for the following types of objects: table, view, trigger, stored procedure, and function.

  • During schema migration, DTS changes the value of the SECURITY attribute from DEFINER to INVOKER for views, stored procedures, and functions.

  • DTS does not migrate user information. To call a view, stored procedure, or function of the destination database, you must grant the read and write permissions to INVOKER.

• Full data migration

  DTS migrates the existing data of objects from the source database to the destination database.

• Incremental data migration

  After full data migration is complete, DTS migrates incremental data from the source database to the destination database. Incremental data migration allows data to be migrated smoothly without interrupting services of self-managed applications during data migration.

SQL operations that can be migrated during incremental data migration

Permissions required for database accounts

For information about how to create a database account and grant permissions to the database account, see the following topics:

• ApsaraDB MyBase for MySQL instance: Create a database account and Manage a database account

• ApsaraDB RDS for MySQL instance: Create an account on an ApsaraDB RDS for MySQL instance and Modify the permissions of a standard account on an ApsaraDB RDS for MySQL instance

Procedure

1. Go to the Data Migration Tasks page.
   1. Log on to the Data Management (DMS) console.
   2. In the top navigation bar, click DTS.
   3. In the left-side navigation pane, choose DTS (DTS) > Data Migration.
   Note

   • Operations may vary based on the mode and layout of the DMS console. For more information, see Simple mode and Customize the layout and style of the DMS console.
   • You can also go to the Data Migration Tasks page of the new DTS console.
2. From the drop-down list next to Data Migration Tasks, select the region in which the data migration instance resides.
   Note If you use the new DTS console, you must select the region in which the data migration instance resides in the upper-left corner.

3. Click Create Task. On the page that appears, configure the source and destination databases.

   Warning

   After you configure the source and destination databases, we recommend that you read the limits displayed at the top of the page. Otherwise, the task may fail or data inconsistency may occur.

   Section	Parameter	Description
   N/A	Task Name	The name of the task. DTS automatically assigns a name to the task. We recommend that you specify a descriptive name that makes it easy to identify the task. You do not need to specify a unique task name.
   Source Database	Select an existing DMS database instance. (Optional. If you have not registered a DMS database instance, ignore this option and configure database settings in the section below.)	The database instance that you want to use. You can choose whether to select an existing instance based on your business requirements. If you select an existing instance, DTS automatically populates the parameters for the database. If you do not select an existing instance, you must manually configure parameters for the database.
   	Database Type	The type of the source database. Select MySQL.
   	Access Method	The access method of the source database. Select Alibaba Cloud Instance.
   	Instance Region	The region where the source ApsaraDB MyBase for MySQL instance resides.
   	Replicate Data Across Alibaba Cloud Accounts	Specifies whether to migrate data across Alibaba Cloud accounts. In this example, No is selected. Note If you want to migrate data across different Alibaba Cloud accounts, you can select Yes. For more information, see Synchronize or migrate data across Alibaba Cloud accounts.
   	RDS Instance ID	The ID of the source ApsaraDB MyBase for MySQL instance.
   	Database Account	The database account of the source ApsaraDB MyBase for MySQL instance. For more information about the permissions that are required for the account, see the "Permissions required for database accounts" section of this topic.
   	Database Password	The password of the database account.
   	Encryption	Specifies whether to encrypt the connection to the source database. Select Non-encrypted or SSL-encrypted based on your business requirements. If you select SSL-encrypted, you must enable SSL encryption for the ApsaraDB MyBase for MySQL instance before you configure the data migration task.
   Destination Database	Select an existing DMS database instance. (Optional. If you have not registered a DMS database instance, ignore this option and configure database settings in the section below.)	In this example, no database instance is selected. Configure the following database information.
   	Database Type	The type of the destination database. Select MySQL.
   	Access Method	The access method of the destination database. Select Alibaba Cloud Instance.
   	Instance Region	The region where the destination ApsaraDB RDS for MySQL instance resides.
   	RDS Instance ID	The ID of the destination ApsaraDB RDS for MySQL instance.
   	Database Account	The database account of the destination ApsaraDB RDS for MySQL instance. For more information about the permissions that are required for the account, see the "Permissions required for database accounts" section of this topic.
   	Database Password	The password of the database account.
   	Encryption	Specifies whether to encrypt the connection to the destination database. Select Non-encrypted or SSL-encrypted based on your business requirements. If you select SSL-encrypted, you must enable SSL encryption for the ApsaraDB RDS for MySQL instance before you configure the data migration task. For more information, see Configure the SSL encryption feature.

4. In the lower part of the page, click Test Connectivity and Proceed.

   If the source or destination database is an Alibaba Cloud database instance, such as an ApsaraDB RDS for MySQL or ApsaraDB for MongoDB instance, DTS automatically adds the CIDR blocks of DTS servers to the IP address whitelist of the instance. If the source or destination database is a self-managed database hosted on an Elastic Compute Service (ECS) instance, DTS automatically adds the CIDR blocks of DTS servers to the security group rules of the ECS instance, and you must make sure that the ECS instance can access the database. If the source or destination database is a self-managed database that is deployed in a data center or provided by a third-party cloud service provider, you must manually add the CIDR blocks of DTS servers to the IP address whitelist of the database to allow DTS to access the database. For more information, see the "CIDR blocks of DTS servers" section of the Add the CIDR blocks of DTS servers to the security settings of on-premises databases topic.

   Warning

   If the CIDR blocks of DTS servers are automatically or manually added to the IP address whitelist of the database instance or ECS security group rules, security risks may arise. Therefore, before you use DTS to migrate data, you must understand and acknowledge the potential risks and take preventive measures, including but not limited to the following measures: enhance the security of your account and password, limit the ports that are exposed, authenticate API calls, regularly check the IP address whitelist or ECS security group rules and forbid unauthorized CIDR blocks, and connect the database to DTS by using Express Connect, VPN Gateway, or Smart Access Gateway.

5. Configure the objects to be migrated and advanced settings.

   Parameter	Description
   Migration Type	To perform only full data migration, select Schema Migration and Full Data Migration. To ensure service continuity during data migration, select Schema Migration, Full Data Migration, and Incremental Data Migration. Note If you do not select Incremental Data Migration, we recommend that you do not write data to the source database during data migration. This ensures data consistency between the source and destination databases.
   Processing Mode of Conflicting Tables	Precheck and Report Errors: checks whether the destination database contains tables that have the same names as tables in the source database. If the source and destination databases do not contain tables that have the same names, the precheck is passed. Otherwise, an error is returned during the precheck and the data migration task cannot be started. Note You can use the object name mapping feature to rename the tables that are migrated to the destination database. You can use this feature if the source and destination databases contain tables that have identical names and the tables in the destination database cannot be deleted or renamed. For more information, see Map object names. Ignore Errors and Proceed: skips the precheck for identical table names in the source and destination databases. Warning If you select Ignore Errors and Proceed, data inconsistency may occur, and your business may be exposed to potential risks. If the source and destination databases have the same schema, DTS does not migrate data records that have the same primary keys as data records in the destination database. If the source and destination databases have different schemas, only specific columns are migrated or the data migration task fails. Proceed with caution. Precheck and Report Errors: checks whether the destination database contains collections that have the same names as collections in the source database. If the source and destination databases do not contain collections that have identical names, the precheck is passed. Otherwise, an error is returned during the precheck and the data migration task cannot be started. Note You can use the object name mapping feature to rename the collections that are migrated to the destination database. You can use this feature if the source and destination databases contain collections that have identical names and the collections in the destination database cannot be deleted or renamed. For more information, see Map object names. Ignore Errors and Proceed: skips the precheck for identical collection names in the source and destination databases. Warning If you select Ignore Errors and Proceed, data inconsistency may occur, and your business may be exposed to potential risks. DTS does not migrate data records that have the same primary keys as data records in the destination database. Data may fail to be initialized, only specific columns are migrated, or the data migration task fails. Precheck and Report Errors: checks whether the destination database contains tables that have the same names as tables in the source database. If the source and destination databases do not contain tables that have the same names, the precheck is passed. Otherwise, an error is returned during the precheck and the data migration task cannot be started. Ignore Errors and Proceed: skips the precheck for identical table names in the source and destination databases. Warning If you select Ignore Errors and Proceed, data inconsistency may occur, and your business may be exposed to potential risks. If the source and destination databases have the same schema, DTS does not migrate data records that have the same primary keys as data records in the destination database. If the source and destination databases have different schemas, only specific columns are migrated or the data migration task fails. Proceed with caution.
   Method to Migrate Triggers in Source Database	The method that is used to migrate triggers from the source database. You can select a migration method based on your business requirements. If no triggers are to be migrated, you do not need to configure this parameter. For more information, see Synchronize or migrate triggers from the source database.
   Enable Migration Assessment	Specifies whether to enable migration assessment. For example, check whether the schemas of the objects to be migrated meet the requirements of the destination database. You can select Yes or No based on your business requirements. Note If you select Yes, the precheck may take more time. You can view the Assessment Result during the precheck. The assessment results do not affect the precheck results.
   Capitalization of Object Names in Destination Instance	The capitalization of database names, table names, and column names in the destination database. By default, DTS default policy is selected. You can select other options to ensure that the capitalization of object names is consistent with that in the source or destination database. For more information, see Specify the capitalization of object names in the destination instance.
   Source Objects	Select one or more objects from the Source Objects section and click the icon to add the objects to the Selected Objects section. Note You can select columns, tables, or databases as the objects to be migrated. If you select tables or columns as the objects to be migrated, DTS does not migrate other objects such as views, triggers, or stored procedures to the destination database.
   Selected Objects	To rename an object that you want to migrate to the destination instance, right-click the object in the Selected Objects section. For more information, see Map the name of a single object. To rename multiple objects at a time, click Batch Edit in the upper-right corner of the Selected Objects section. For more information, see Map multiple object names at a time. Note If you use the object name mapping feature to rename an object, other objects that are dependent on the object may fail to be migrated. To specify WHERE conditions to filter data, right-click an object in the Selected Objects section. In the dialog box that appears, specify the conditions. For more information, see Use SQL conditions to filter data. To migrate DML or DDL operations performed on a specific database or table, right-click the object in the Selected Objects section. In the dialog box that appears, select the DML or DDL operations on which you want to perform incremental data migration. For more information about the operations, see the "SQL operations that can be migrated during incremental data migration" section of this topic.

6. Click Next: Advanced Settings to configure advanced settings.

   • Data Verification Settings

     For more information about how to enable data verification, see Enable data verification.

   • Advanced settings

     Parameter	Description
     Set Alerts	Specifies whether to set alerts for the data migration task. If the task fails or the migration latency exceeds the threshold, the alert contacts will receive notifications. Valid values: No: does not set alerts. Yes: sets alerts. If you select Yes, you must also set the alert threshold and alert contacts. For more information,see Configure monitoring and alerting when you create a DTS task.
     Copy the temporary table of the Online DDL tool that is generated in the source table to the destination database	If you use DMS or the gh-ost tool to perform online DDL operations on the source database, you can specify whether to migrate the temporary tables generated by online DDL operations. Valid values: Important You cannot use tools such as pt-online-schema-change to perform online DDL operations on the source database. Otherwise, the DTS task fails. Yes: DTS migrates the data of temporary tables generated by online DDL operations. Note If online DDL operations generate a large amount of data, the data migration task may take an extended period of time to complete. No, Adapt to DMS Online DDL: DTS does not migrate the data of temporary tables generated by online DDL operations. Only the original DDL operations that are performed by using DMS are migrated. Note If you select No, Adapt to DMS Online DDL, the tables in the destination database may be locked. No, Adapt to gh-ost: DTS does not migrate the data of temporary tables generated by online DDL operations. Only the original DDL operations that are performed by using the gh-ost tool are migrated. You can use the default or custom regular expressions to filter out the shadow tables of the gh-ost tool and tables that are not required. Note If you select No, Adapt to gh-ost, the tables in the destination database may be locked.
     Whether to Migrate Accounts	Specifies whether to migrate the account information of the source database based on your business requirements. If you select Yes, you must select the accounts that you want to migrate and check the permissions of the source and destination database accounts used in the data migration task. Important The source and destination database accounts used in the data migration task must have the SELECT permission on the mysql.user, mysql.db, mysql.columns_priv, and mysql.tables_priv metadata tables. The accounts that already exist in the destination database and the system accounts of the source database, such as root, mysql.infoschema, mysql.session, and mysql.sys, cannot be migrated.
     Retry Time for Failed Connections	The retry time range for failed connections. If the source or destination database fails to be connected after the data migration task is started, DTS immediately retries a connection within the retry time range. Valid values: 10 to 1440. Unit: minutes. Default value: 720. We recommend that you set the parameter to a value greater than 30. If DTS reconnects to the source and destination databases within the specified retry time range, DTS resumes the data migration task. Otherwise, the data migration task fails. Note If you set different retry time ranges for multiple data migration tasks that share the same source or destination instance, the value that is set later takes precedence. When DTS retries a connection, you are charged for the DTS instance. We recommend that you specify the retry time range based on your business requirements. You can also release the DTS instance at your earliest opportunity after the source database and destination instances are released.
     The wait time before a retry when other issues occur in the source and destination databases.	The retry time range for other issues. For example, if the DDL or DML operations fail to be performed after the data migration task is started, DTS immediately retries the operations within the time range. Valid values: 1 to 1440. Unit: minutes. Default value: 10. We recommend that you set the parameter to a value greater than 10. If the failed operations are successfully performed within the specified time range, DTS resumes the data migration task. Otherwise, the data migration task fails. Important The value of the The wait time before a retry when other issues occur in the source and destination databases parameter must be smaller than the value of the Retry Time for Failed Connections parameter.
     Configure ETL	Specifies whether to configure the extract, transform, and load (ETL) feature. For more information, see What is ETL? Valid values: Yes: configures the ETL feature. You can enter data processing statements in the code editor. For more information, see Configure ETL in a data migration or data synchronization task. No: does not configure the ETL feature.

7. In the lower part of the page, click Next: Save Task Settings and Precheck.

   You can move the pointer over Next: Save Task Settings and Precheck and click Preview OpenAPI parameters to view the parameters to be specified when you call the relevant API operation to configure the DTS task.

   Note

   • Before you can start the data migration task, DTS performs a precheck. You can start the data migration task only after the task passes the precheck.

   • If the task fails to pass the precheck, click View Details next to each failed item. After you troubleshoot the issues based on the causes, run a precheck again.

   • If an alert is triggered for an item during the precheck:

     • If an alert item cannot be ignored, click View Details next to the failed item and troubleshoot the issues. Then, run a precheck again.

     • If an alert item can be ignored, click Confirm Alert Details. In the View Details dialog box, click Ignore. In the message that appears, click OK. Then, click Precheck Again to run a precheck again. If you ignore the alert item, data inconsistency may occur, and your business may be exposed to potential risks.

8. Wait until the Success Rate value becomes 100%. Then, click Next: Purchase Instance.

9. On the Purchase Instance page, specify the Instance Class parameter for the data migration instance. The following table describes the parameter.

   Section	Parameter	Description
   New Instance Class	Resource Group	The resource group to which the data migration instance belongs. Default value: default resource group. For more information, see What is Resource Management?.
   	Instance Class	DTS provides various instance classes that vary in the migration speed. You can select an instance class based on your business scenario. For more information, see Specifications of data migration instances.

10. Read and select the check box to agree to Data Transmission Service (Pay-as-you-go) Service Terms.

11. Click Buy and Start to start the data migration task. You can view the progress of the task in the task list.