Data Transmission Service (DTS) classifies each instance as same-region, cross-region, or cross-border based on where the source and destination databases are located. Knowing your instance type helps you plan network connectivity and anticipate billing differences before you configure a task.
Region groups
DTS groups all regions into two categories:
Regions in China: the Chinese mainland, China (Hong Kong), China (Macao), and China (Taiwan)
Regions outside China: all other regions
Instance types
The instance type is determined by the combination of source and destination regions.
| Source region | Destination region | Instance type |
|---|---|---|
| Chinese mainland | Chinese mainland (same region) | Same-region |
| Chinese mainland | Chinese mainland (different region) | Cross-region |
| Chinese mainland | China (Hong Kong), China (Macao), China (Taiwan), or outside China | Cross-border |
| China (Hong Kong) | Chinese mainland | Cross-border |
| China (Hong Kong) | China (Hong Kong) | Same-region |
| China (Hong Kong) | China (Macao), China (Taiwan), or outside China | Cross-region |
| China (Macao) | Chinese mainland | Cross-border |
| China (Macao) | China (Macao) | Same-region |
| China (Macao) | China (Hong Kong), China (Taiwan), or outside China | Cross-region |
| China (Taiwan) | Chinese mainland | Cross-border |
| China (Taiwan) | China (Taiwan) | Same-region |
| China (Taiwan) | China (Hong Kong), China (Macao), or outside China | Cross-region |
| Outside China | Chinese mainland | Cross-border |
| Outside China | Outside China (same region) | Same-region |
| Outside China | China (Hong Kong), China (Macao), China (Taiwan), or outside China (different region) | Cross-region |
The rule in short: a cross-border instance has its source and destination on opposite sides of the China border. A cross-region instance has both ends on the same side of the border but in different regions. A same-region instance has both ends in the same region.
Examples
| Scenario | Source | Destination | Instance type |
|---|---|---|---|
| Migrate within the Chinese mainland | China (Beijing) | China (Shanghai) | Cross-region |
| Migrate from the Chinese mainland to Hong Kong | China (Hangzhou) | China (Hong Kong) | Cross-border |
| Sync between two overseas regions | Singapore | Germany (Frankfurt) | Cross-region |
| Replicate within Hong Kong | China (Hong Kong) | China (Hong Kong) | Same-region |
| Migrate from Hong Kong to Singapore | China (Hong Kong) | Singapore | Cross-region |
Prerequisites
Cross-border and cross-region data migration instances require public network connectivity between DTS and your databases. The specific requirement depends on how the source database is accessed:
If Access Method is set to Alibaba Cloud Instance for the source database, the source database must have a public endpoint.
If Access Method is not set to Alibaba Cloud Instance for the source database, the destination database must have a public endpoint.