After you create a sandbox instance, you can use Data Transmission Service (DTS) to migrate data from the sandbox instance to an ApsaraDB RDS for MySQL instance.
Background information
Database Backup (DBS) provides the sandbox feature based on copy data management (CDM). You can use this feature to quickly create independent sandbox instances with ease. This way, your backup data is quickly available. For more information, see DBS sandbox overview.
After you create a sandbox instance, you can use DTS to migrate data from the sandbox instance to an ApsaraDB RDS for MySQL instance. This operation applies to the following scenarios:
Save the data that is written in a sandbox instance. Read and write operations performed on sandbox instances do not affect source databases. To save the data that is written to a sandbox instance, you can migrate the data from the sandbox instance to an ApsaraDB RDS for MySQL instance.
Accelerate restoration. Compared with the regular restoration methods provided by DBS, the sandbox feature accelerates the restoration of backup sets. You can use the sandbox instance feature to create a sandbox instance for emergency disaster recovery and then migrate the tables or databases in the sandbox instance to an ApsaraDB RDS for MySQL instance.
Prerequisites
The sandbox instance is restored. For more information, see Use the emergency recovery feature for 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 to be migrated. For more information, see Change instance specifications.
Usage notes
Data migration does not affect the data in the sandbox instance. During data migration, DTS reads the data in the sandbox instance and copies the data to the ApsaraDB RDS for MySQL instance. DTS does not delete data from the sandbox instance.
To ensure data consistency, we recommend that you do not write data to the sandbox instance during full data migration.
For more information, see Limits section of the "Migrate data from a self-managed MySQL database to an ApsaraDB RDS for MySQL instance" topic.
Billing
Migration type | Instance configuration fee | Internet traffic fee |
Schema migration and full data migration | Free of charge. | Charged only when data is migrated from Alibaba Cloud over the Internet. For more information, see Billing overview. |
Incremental data migration | Charged. For more information, see Billing overview. |
Procedure
Go to the Data Migration Tasks page.
Log on to the Data Management (DMS) console.
In the top navigation bar, move the pointer over DTS.
Choose .
NoteThe actual 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 page of the new DTS console.
From the drop-down list on the right side of Data Migration Tasks, select the region in which your data migration instance resides.
NoteIf you use the new DTS console, you must select the region in which the data migration instance resides in the upper-left corner.
Click Create Task. In the Create Task wizard, configure the source and destination databases. The following table describes the parameters.
WarningAfter you configure the source and destination databases, we recommend that you read the Limits that are displayed in the upper part of the page. Otherwise, the task may fail or data inconsistency may occur.
Section
Parameter
Example
N/A
Task Name
The name of the task. DTS automatically generates a task name. We recommend that you specify an informative name to identify the task. You do not need to specify a unique task name.
Source Database
Select a DMS database instance
The instance that you want to use. You can choose whether to use 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 configure parameters for the source database.
Database Type
The type of the source database. Select MySQL.
Access Method
The access method of the source database. Select Express Connect, VPN Gateway, or Smart Access Gateway.
Instance Region
The region in which the sandbox instance resides.
Replicate Data Across Alibaba Cloud Accounts
Specifies whether to migrate data across Alibaba Cloud accounts. In this example, No is selected.
Connected VPC
The virtual private cloud (VPC) that is used to connect to the sandbox instance. You can query the VPC on the VPC page.
IP Address or Domain Name
The endpoint of the sandbox instance. You can view the endpoint on the details page of the sandbox instance.
Port Number
The port number that is used to connect to the sandbox instance. Default value: 3306.
Database Account
The database account of the sandbox instance. For more information, see the Permissions required for database accounts section of the "Migrate data from a self-managed MySQL database to an ApsaraDB RDS for MySQL instance" topic.
NoteThe database account and password of the sandbox instance must be consistent with those of the source database whose data was backed up to the sandbox instance.
Database Password
The password that is used to access the database instance.
Encryption
Specifies whether to encrypt the connection to the database. You can select Non-encrypted or SSL-encrypted based on your business requirements. If you want to set this parameter to SSL-encrypted, you must enable SSL encryption for the ApsaraDB RDS for MySQL instance before you configure the DTS task. For more information, see Use a cloud certificate to enable SSL encryption.
Destination Database
Select a DMS database instance
The instance that you want to use. You can choose whether to use an existing instance based on your business requirements.
If you select an existing instance, DTS automatically populates the parameters for the instance.
If you do not select an existing instance, you must configure parameters for the destination database.
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 in which the destination ApsaraDB RDS 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.
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 the "Migrate data from a self-managed MySQL database to an ApsaraDB RDS for MySQL instance" topic.
Database Password
The password that is used to access the database instance.
Encryption
Specifies whether to encrypt the connection to the source database instance. Select Non-encrypted or SSL-encrypted based on your business requirements. If you want to set this parameter to SSL-encrypted, you must enable SSL encryption for the ApsaraDB RDS for MySQL instance before you configure the DTS task. For more information, see Use a cloud certificate to enable SSL encryption.
In the lower part of the page, click Test Connectivity and Proceed.
If an IP address whitelist is configured for your self-managed database, add the CIDR blocks of DTS servers to the IP address whitelist. Then, click Test Connectivity.
WarningIf the public CIDR blocks of DTS servers are automatically or manually added to the whitelist of a database instance or to the security group rules of an ECS instance, 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: enhancing the security of your username and password, limiting the ports that are exposed, authenticating API calls, regularly checking the whitelist or security group rules and forbidding unauthorized CIDR blocks, or connecting the database instance to DTS by using Express Connect, VPN Gateway, or Smart Access Gateway.
Configure the objects to be migrated.
On the Select Objects page, configure the objects that you want to migrate.
Parameter
Description
Migration Types
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.
NoteIf 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.
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.
NoteThis parameter is available only if you select Schema Migration and Incremental Data Migration for the Migration Types parameter.
Enable Migration Assessment
Specifies whether to enable migration assessment. Migration assessment aims to check whether the schemas of the source and destination databases, such as the length of indexes, stored procedures, and dependent tables, meet the requirements. You can select Yes or No based on your business requirements.
NoteYou can configure this parameter only if you select Schema Migration for the Migration Types parameter.
If you select Yes, the precheck may take more time. You can view Assessment Result during the precheck. The assessment results do not affect the precheck results.
Processing Mode of Conflicting Tables
Precheck and Report Errors: checks whether the destination database contains tables that use the same names as tables in the source database. If the source and destination databases do not contain tables that have identical table names, the precheck is passed. Otherwise, an error is returned during the precheck and the data migration task cannot be started.
NoteIf the source and destination databases contain tables with identical names and the tables in the destination database cannot be deleted or renamed, you can use the object name mapping feature to rename the tables that are migrated to the destination database. For more information, see Map object names.
Ignore Errors and Proceed: skips the precheck for identical table names in the source and destination databases.
WarningIf you select Ignore Errors and Proceed, data inconsistency may occur and your business may be exposed to the following potential risks:
If the source and destination databases have the same schema, and a data record has the same primary key as an existing data record in the destination database, the following scenarios may occur:
During full data migration, DTS does not migrate the data record to the destination database. The existing data record in the destination database is retained.
During incremental data migration, DTS migrates the data record to the destination database. The existing data record in the destination database is overwritten.
If the source and destination databases have different schemas, only specific columns are migrated or the data migration task fails. Proceed with caution.
Capitalization of Object Names in Destination Instance
The capitalization of database names, table names, and column names in the destination instance. By default, DTS default policy is selected. You can select other options to make sure that the capitalization of object names is consistent with that of 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. Click the icon and add the objects to the Selected Objects section.
NoteYou 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.
NoteIf 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 a table in the Selected Objects section. In the dialog box that appears, specify the conditions. For more information, see Specify filter conditions.
To select the SQL operations performed on a specific database or table, right-click an object in the Selected Objects section. In the dialog box that appears, select the SQL operations that you want to migrate. For more information about the SQL operations that support incremental migration, see the SQL operations that support incremental migration section of this topic.
Click Next: Advanced Settings to configure advanced settings.
Parameter
Description
Dedicated Cluster for Task Scheduling
By default, DTS schedules the data migration task to the shared cluster if you do not specify a dedicated cluster. If you want to improve the stability of data migration tasks, purchase a dedicated cluster. For more information, see What is a DTS dedicated cluster.
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 data of temporary tables generated by online DDL operations. Valid values:
ImportantYou 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.
NoteIf online DDL operations generate a large amount of data, latency may occur for the data migration task.
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.
NoteIf you select this option, 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.
NoteIf you select this option, the tables in the destination database may be locked.
Whether to Migrate Accounts
Specifies whether to migrate the account information of the source database. You can configure this parameter 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.
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 is reconnected to the source and destination databases within the specified retry time range, DTS resumes the data migration task. Otherwise, the data migration task fails.
NoteIf you specify different retry time ranges for multiple data migration tasks that share the same source or destination database, the value that is specified 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 the earliest opportunity after the source database and destination instance are released.
Retry Time for Other Issues
The retry time range for other issues. For example, if DDL or DML operations fail to be performed after the data migration task is started, DTS immediately retries the operations within the retry 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 retry time range, DTS resumes the data migration task. Otherwise, the data migration task fails.
ImportantThe value of the Retry Time for Other Issues parameter must be smaller than the value of the Retry Time for Failed Connections parameter.
Enable Throttling for Full Data Migration
Specifies whether to enable throttling for full data migration. During full data migration, DTS uses the read and write resources of the source and destination databases. This may increase the loads of the database servers. You can enable throttling for full data migration based on your business requirements. To configure throttling, you must configure the Queries per second (QPS) to the source database, RPS of Full Data Migration, and Data migration speed for full migration (MB/s) parameters. This reduces the loads of the destination database server.
NoteYou can configure this parameter only if you select Full Data Migration for the Migration Types parameter.
Enable Throttling for Incremental Data Migration
Specifies whether to enable throttling for incremental data migration. To configure throttling, you must configure the RPS of Incremental Data Migration and Data migration speed for incremental migration (MB/s) parameters. This reduces the loads of the destination database server.
NoteYou can configure this parameter only if you select Incremental Data Migration for the Migration Types parameter.
Environment Tag
The environment tag that is used to identify the DTS instance. You can select an environment tag based on your business requirements. In this example, you do not need to configure this parameter.
Whether to delete SQL operations on heartbeat tables of forward and reverse tasks
Specifies whether to write SQL operations on heartbeat tables to the source database while the DTS instance is running. Valid values:
Yes: does not write SQL operations on heartbeat tables. In this case, a latency of the DTS instance may be displayed.
No: writes SQL operations on heartbeat tables. In this case, features such as physical backup and cloning of the source database may be affected.
Configure ETL
Specifies whether to enable 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.
Monitoring and Alerting
Specifies whether to configure alerting for the data migration task. If the task fails or the migration latency exceeds the specified threshold, the alert contacts receive notifications. Valid values:
No: does not configure alerting.
Yes: configures alerting. In this case, you must also configure the alert threshold and alert notification settings. For more information, see the Configure monitoring and alerting when you create a DTS task section of the Configure monitoring and alerting topic.
Click Next Step: Data Verification to configure the data verification task.
For more information about how to use the data verification feature, see Configure a data verification task.
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.
NoteBefore 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 analyze the causes based on the check results, troubleshoot the issues. Then, 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 the 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.
Wait until Success Rate becomes 100%. Then, click Next: Purchase Instance.
On the Purchase Instance page, configure the Instance Class parameter for the data migration instance. The following table describes the parameters.
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 instance classes that vary in the migration speed. You can select an instance class based on your business scenario. For more information, see Instance classes of data migration instances.
Read and agree to Data Transmission Service (Pay-as-you-go) Service Terms by selecting the check box.
Click Buy and Start. In the message that appears, click OK.
You can view the progress of the task on the Data Migration page.