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

Source database requirements

• Tables must have a PRIMARY KEY or UNIQUE constraint with all fields unique. Otherwise, the destination database may contain duplicate records.

• When migrating individual tables (not entire databases), a single migration task supports up to 1,000 tables. For larger migrations, split the tables across multiple tasks or migrate the entire database instead.

• For incremental data migration, configure binary logging as follows:

  Important

  Set the binary log retention period based on your migration type:

  • Incremental migration only: retain binary logs for more than 24 hours

  • Full + incremental migration: retain binary logs for at least 7 days

  If DTS cannot obtain the required binary logs, the task fails. In exceptional circumstances, data inconsistency or loss may occur. After full data migration completes, you can reduce the retention period to more than 24 hours.

  Parameter	Required value
  Binary logging	Enabled
  binlog_format	row
  binlog_row_image	full

• During schema migration and full data migration, do not run DDL operations that change database or table schemas. This causes the migration task to fail.

• During full and incremental data migration, DTS temporarily disables foreign key constraint checks and cascade operations at the session level. Running cascade or delete operations on the source database during this period may cause data inconsistency.

• If you run full data migration only (without incremental), do not write to the source database while migration is running.

General limitations

• Use the same MySQL engine version for source and destination to avoid compatibility issues.

• DTS uses ROUND(COLUMN,PRECISION) to retrieve values from FLOAT and DOUBLE columns. If you do not specify a precision, DTS applies 38 digits for FLOAT and 308 digits for DOUBLE. Verify that these precision settings meet your requirements.

• DTS automatically creates the destination database unless the source database name is invalid. If the source database name is invalid, create the database manually before configuring the task.

• DTS resumes failed tasks for up to 7 days. Before switching workloads to the destination, stop or release any failed tasks. Alternatively, run REVOKE to remove the DTS account's write permissions on the destination — otherwise the source data overwrites the destination after the task resumes.

• DTS updates the dts_health_check.ha_health_check table in the source database periodically to advance the binary log position.

• Full data migration uses concurrent INSERT operations, which causes table fragmentation in the destination. After full migration, the destination tablespace is larger than the source.

SQL operations supported for incremental migration

Step 1: Open the data migration page

Use one of the following methods to open the Data Migration page.

DTS console

1. Log on to the DTS console.

2. In the left-side navigation pane, click Data Migration.

3. In the upper-left corner, select the region where the migration instance will run.

DMS console

The exact navigation path varies based on your DMS console layout. For more information, see Simple mode and Customize the layout and style of the DMS console.

1. Log on to the DMS console.

2. In the top navigation bar, go to Data Development > DTS (DTS) > Data Migration.

3. From the drop-down list next to Data Migration Tasks, select the region where the migration instance will run.

Step 2: Create a task

Click Create Task to open the task configuration page.

If the page shows New Configuration Page in the upper-right corner, click it to switch to the new interface. Skip this if Back to Previous Version is already displayed.

Specific parameters differ between the new and previous configuration page versions. Use the new version.

Step 3: Configure source and destination databases

Configure the following parameters for the source and destination databases.

Source database (ApsaraDB MyBase for MySQL)

Destination database (ApsaraDB RDS for MySQL)

Step 4: Test connectivity

Click Test Connectivity and Proceed.

DTS automatically adds its server CIDR blocks to the IP address whitelist of Alibaba Cloud database instances and to the security group rules of Elastic Compute Service (ECS) instances.

If the source or destination is a self-managed database in a data center or hosted by a third-party provider, manually add the DTS server CIDR blocks to the database's IP address whitelist. For self-managed databases hosted on ECS instances, DTS adds the CIDR blocks to the security group rules automatically for single-ECS deployments; for multi-ECS deployments, add the CIDR blocks to each ECS instance's security group rules manually. See Add the CIDR blocks of DTS servers.

Step 5: Configure migration objects

On the Configure Objects page, set the following parameters.

Migration types

Select the migration types to run:

• Schema Migration + Full Data Migration: migrates schema and existing data only; stops when the initial copy is complete.

• Schema Migration + Full Data Migration + Incremental Data Migration (recommended): migrates schema and data, then continuously replicates changes until you stop the task. Use this combination to minimize downtime.

If you run full data migration without incremental, do not write to the source database during migration.

Object configuration parameters

Click Next: Advanced Settings.

Advanced settings

Click Next Step: Data Verification to configure data verification. For details, see Configure a data verification task.

Step 6: Run the precheck

Click Next: Save Task Settings and Precheck.

DTS runs a precheck before starting migration. To preview the API parameters for this configuration, hover over the button and click Preview OpenAPI parameters before proceeding.

• If the precheck passes, the task starts automatically.

• If any item fails, click View Details to see the cause, fix the issue, and click Precheck Again.

• If an alert appears for an item that can be safely ignored: click Confirm Alert Details, then Ignore in the dialog, then OK, and run the precheck again. Ignoring an alert may cause data inconsistency.

Step 7: Purchase a migration instance

On the Purchase Instance page, configure the instance class.

Read and accept the Data Transmission Service (Pay-as-you-go) Service Terms, then click Buy and Start and confirm with OK.

Track migration progress on the Data Migration page.