How do I create a similar instance? - Data Transmission Service

Data Transmission Service (DTS) allows you to use some configurations of an existing data synchronization or migration instance as the default configurations of a new DTS instance. This helps you create DTS instances with similar configurations in a convenient and fast manner. When you create a similar instance, you can modify the configurations as required.

Prerequisites

A data synchronization or migration instance is created and configured as the existing DTS instance.
The existing DTS instance is in the Precheck stage or later and is displayed on the Data Synchronization Tasks or Data Migration Tasks page.

Usage notes

When you create a similar instance based on an existing DTS instance, DTS retains only some configurations of the existing DTS instance and you must manually complete the configurations of the new DTS instance. You can also modify the retained configurations. You cannot specify the configurations to be retained.
Make sure that the objects selected in the Configure Objects and Advanced Settings step exist in the source database and the destination database can receive data as expected.

Procedure

The procedure for creating a similar data synchronization instance is the same as that for creating a similar data migration instance. In this example, a similar data synchronization instance is created.

Go to the Data Synchronization Tasks page.
1. Log on to the DMS console.
2. In the top navigation bar, click DTS.
3. In the left-side navigation pane, choose DTS (DTS) > Data Synchronization.
Note
- The actual operation may vary depending on the mode and layout of DMS. For more information, see Simple mode and Customize the layout and style of the DMS console.
- You can also go to the Data Synchronization Tasks page of the new DTS console.
From the drop-down list to the right of Data Synchronization Tasks, select the region in which you want to create the data synchronization task.
Note
If you use the new DTS console, select the region in which you want to create the data synchronization task in the upper-left corner of the page.
Find the DTS instance based on which you want to create a similar instance. Click the icon and select Duplicate Task in the Actions column.
Configure the source and destination databases.
Check whether the default configurations meet your business requirements. You can modify the parameters as required.
Important
- By default, the name of the new DTS instance is the same as that of the existing DTS instance. We recommend that you specify a descriptive name for easy identification. You do not need to specify a unique name.
- If the source database is an ApsaraDB RDS for SQL Server instance, the Database Account parameter is set to rdsdt_dtsacct by default, which is the built-in account created by DTS. You must change the account to the database account of the source ApsaraDB RDS for SQL Server instance.
- You must make sure that DTS can connect to the source and destination databases based on the configuration information and that the database accounts used in the DTS task have the required permissions.Database Account
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 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 ensure 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 whitelist of the database to allow DTS to access the database. For more information, see Add the CIDR blocks of DTS servers to the security settings of on-premises databases.
Warning
If the CIDR blocks of DTS servers are automatically or manually added to the whitelist of the database or instance, or to the ECS security group rules, security risks may arise. Therefore, before you use DTS to synchronize 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 ECS security group rules and forbidding unauthorized CIDR blocks, or connecting the database to DTS by using Express Connect, VPN Gateway, or Smart Access Gateway.
Select the objects to be synchronized and configure advanced settings.
- Parameters with default configurations: Check whether the default configurations meet your business requirements. You can modify the parameters as required.
- Unconfigured parameters: Configure the parameters as required.
Click Next: Advanced Settings to configure advanced settings.
- Data Verification Settings
  You can modify only the Data Verification Mode and Verification Objects parameters. For more information, see What is data verification?
- Advanced Settings
  Configure the parameters as required. For more information, see Overview of data synchronization scenarios or Overview of data migration scenarios.
Click Next: Save Task Settings and Precheck in the lower part of the page.
You can move the pointer over Next: Save Task Settings and Precheck and click Preview OpenAPI parameters to view the parameter settings of the API operation that is called to configure the instance.
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, 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.
Perform subsequent steps as prompted.

FAQ

Am I able to create a similar instance based on an existing change tracking instance?
No, you cannot create a similar instance based on an existing change tracking instance.
Am I able to create a similar instance based on a released DTS instance?
No, you cannot create a similar instance based on a released DTS instance. After a DTS instance is released, it is deleted from the Data Synchronization Tasks or Data Migration Tasks page and can no longer be managed.
Am I able to create a similar instance by using the API?
No, you cannot create a similar instance by using the API.
Am I able to create an identical instance based on an existing DTS instance with a few clicks?
No, you cannot create an identical instance based on an existing DTS instance with a few clicks.