ApsaraDB for MongoDB provides standalone instances, replica set instances, and sharded cluster instances. Standalone instances are designed to store non-core enterprise data, such as data in development and testing scenarios. Replica set instances and sharded cluster instances are more suitable for production scenarios. This topic describes how to migrate data from a standalone instance to a replica set instance or a sharded cluster instance by using Data Transmission Service (DTS).

Prerequisites

The available storage space of the destination instance is larger than the total size of the data in the source instance.

Precautions

  • DTS consumes the resources of the source and destination instances during full data migration. This may increase the loads of the database servers. If you migrate a large volume of data or the server specifications cannot meet your requirements, database services may become unavailable. Before you migrate data, evaluate the impact of data migration on the performance of the source and destination databases. We recommend that you migrate data during off-peak hours.
  • DTS does not support incremental data migration from a standalone instance. To ensure data consistency, do not write data to the source instance during full data migration.
  • If the source and destination MongoDB databases use different versions or storage engines, make sure that your applications can run on both databases. For more information about the versions and storage engines that are supported by ApsaraDB for MongoDB, see MongoDB versions and storage engines.
  • To ensure better performance and stability of the instance, the system will upgrade the minor version to the latest version by default. If the minor version of your instance expires or is not included in the maintenance list and the instance is upgraded, migrated, changed, Created from a backup, Created by point-in-time, or performed Restore data to a new ApsaraDB for MongoDB instance.
  • The admin or local database cannot be used as the source or destination database.

Billing

Migration type Task configuration fee Internet traffic fee
Full data migration Free of charge Free of charge

Migration types

Full data migration: DTS migrates all historical data of the source MongoDB database to the destination MongoDB database.

Note The following types of objects are supported: database, collection, and index.

Permissions required for database accounts

Instance Permission
Source ApsaraDB for MongoDB instance The read permissions on the source database
Destination ApsaraDB for MongoDB instance The read and write permissions on the destination database

For more information about how to create and authorize a database account, see Manage user permissions on MongoDB databases.

Procedure

  1. Log on to the DTS console.
  2. In the left-side navigation pane, click Data Migration.
  3. At the top of the Migration Tasks page, select the region where the destination ApsaraDB for MongoDB instance resides.
    Select a region
  4. In the upper-right corner of the page, click Create Migration Task.
  5. Configure the source and destination databases.
    Configure the source and destination databases
    Section Parameter Description
    N/A Task Name DTS automatically generates a task name. We recommend that you specify an informative name for easy identification. You do not need to use a unique task name.
    Source Database Instance Type Select ApsaraDB for MongoDB.
    Instance Region Select the region where the source ApsaraDB for MongoDB instance resides.
    MongoDB Instance ID Select the ID of the source ApsaraDB for MongoDB instance.
    Database Name Enter the name of the authentication database. The database account is created in this database.
    Database Account Enter the database account of the source ApsaraDB for MongoDB instance. For more information about the permissions that are required for the account, see Permissions required for database accounts.
    Database Password Enter the password of the database account.
    Note After you specify the source database parameters, click Test Connectivity next to Database Password to verify whether the specified parameters are valid. If the specified parameters are valid, the Passed message appears. If the Failed message appears, click Check next to Failed. Modify the source database parameters based on the check results.
    Destination Database Instance Type Select MongoDB Instance.
    Instance Region Select the region where the destination ApsaraDB for MongoDB instance resides.
    MongoDB Instance ID Select the ID of the destination ApsaraDB for MongoDB instance.
    Database Name Enter the name of the authentication database. The database account is created in this database.
    Database Account Enter the database account of the destination ApsaraDB for MongoDB instance. For more information about the permissions that are required for the account, see Permissions required for database accounts.
    Database Password Enter the password of the database account.
    Note After you specify the destination database parameters, click Test Connectivity next to Database Password to verify whether the specified parameters are valid. If the specified parameters are valid, the Passed message appears. If the Failed message appears, click Check next to Failed. Modify the destination database parameters based on the check results.
  6. In the lower-right corner, click Set Whitelist and Next.
    Note DTS adds the CIDR blocks of DTS servers to the whitelists of the source and destination ApsaraDB for MongoDB instances. This ensures that DTS servers can connect to the source and destination ApsaraDB for MongoDB instances. After data migration is complete, you can remove the CIDR blocks of DTS servers from the whitelists. For more information, see Configure a whitelist for a sharded cluster instance.
  7. Select the migration types and the objects to be migrated.
    Setting Description
    Select the migration types Select Full Data Migration.
    Note If the data source is a standalone instance, you can select only Full Data Migration. To ensure data consistency, do not write data to the source instance during full data migration.
    Select the objects to be migrated
    • Select one or more objects from the Available section and click the icon to move the objects to the Selected section.
      Note DTS cannot migrate data from the admin or local database.
    • You can select databases, collections, or functions as the objects to be migrated.
    • By default, after an object is migrated to the destination database, the name of the object remains unchanged. You can use the object name mapping feature to rename the objects that are migrated to the destination database. For more information, see Object name mapping.
    Specify whether to rename objects You can use the object name mapping feature to rename the objects that are migrated to the destination instance. For more information, see Object name mapping.
    Specify the retry time for failed connections to the source or destination database By default, if DTS fails to connect to the source or destination database, DTS retries within the next 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 migration task. Otherwise, the data migration 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.
  8. In the lower-right corner of the page, click Precheck.
    Note
    • Before you can start the data migration task, a precheck is performed. You can start the data migration 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.
  9. After the task passes the precheck, click Next.
  10. In the Confirm Settings dialog box, specify the Channel Specification parameter and select Data Transmission Service (Pay-As-You-Go) Service Terms.
  11. Click Buy and Start to start the data migration task.
    Note We recommend that you do not manually stop a data migration task. Otherwise, data migrated to the destination instance will be incomplete. You can wait until the data migration task automatically stops.
  12. Switch your workloads to the destination ApsaraDB for MongoDB instance.

References