This topic describes the differences between the following concepts for data replication: data migration, synchronization, and recovery.
Data Migration, synchronization, and recovery have the following differences:
- Differences between data migration and data restoration
Although data migration and restoration both can be used to replicate data to a new RDS instance, they differ in the following aspects:
- The data migration feature enables you to use Alibaba Cloud Data transmission service (DTS) to migrate data from an on-premises database, a user-created database on an ECS instance, or a database on a third-party cloud platform to Alibaba Cloud. This feature also enables you to migrate data from Alibaba Cloud to a user-created database.
- The data restoration solution enables you to restore an RDS instance from a data backup file, or restore an RDS instance to a specific point in time by using a data backup file and a binary log file.
You can use the data migration and restoration solutions together to meet your business needs. For example, you can restore an RDS instance to a new instance and then use DTS to migrate the data back to the original RDS instance. This way, you do not need to update the endpoints on your application.
Note The data restoration solution provided in the ApsaraDB for RDS console meets most business needs for data restoration and some business needs for data migration. However, it does not support incremental data migration. - Comparison between data migration and synchronization
- The data migration solution is used to migrate data to Alibaba Cloud. If you select the incremental data migration option when you create a migration task, the data updated in the original RDS instance is synchronized to the new RDS instance. However, this solution is different from the data synchronization solution, which supports more functions such as online updates of synchronized objects and two-way data synchronization. You can release a data migration task immediately after it is complete.
- The data synchronization solution is used to synchronize data between two data sources in real time. It is suitable for various scenarios such as active geo-redundancy, disaster recovery, cross-border data synchronization, query load balancing, cloud BI systems, and real-time data warehousing. After you create a data synchronization task, it keeps synchronizing data between the specified data sources to ensure data consistency.