Async replication supports Replication Time Control (RTC) to provide a data replication service with a recovery point objective (RPO) of 10 minutes or less. This service enhances disaster recovery reliability and helps you meet requirements for data security and classified protection compliance.
Usage notes
Supported regions:
Replication across zones in the same region: RTC is supported for replication tasks between different zones in the same region.
Cross-region replication:
RTC is supported for cross-region replication tasks only between the following regions: China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Shenzhen), China (Ulanqab), China (Heyuan), China (Guangzhou), and China (Chengdu).
For industry clouds, RTC is supported for cross-region replication tasks only between China East 2 Finance, China North 2 Finance (Preview), and China South 1 Finance.
Maximum supported write data volume: The total data written to the primary disk of a single replication pair must be less than 60 GB within any 5-minute period.
Enable RTC for an async replication pair
Create an async replication pair
When you create an async replication pair, set Enable Replication Time Control (RTC) to Yes to enable RTC.
Modify an existing async replication pair
Log on to the Elastic Block Storage (EBS) console. In the top navigation bar, select the region where the target instance is located.
In the navigation pane on the left, choose .
In the Replication Time Control (RTC) column for the target replication pair, enable RTC.
You cannot enable RTC for an individual replication pair that is part of a replication group.
Disable RTC for an async replication pair
Log on to the EBS console. In the top navigation bar, select the region where the target instance is located.
In the navigation pane on the left, choose .
In the Replication Time Control (RTC) column for the target replication pair, disable RTC.
The operation to disable RTC can take up to 10 minutes.
You cannot disable RTC for an individual replication pair that is part of a replication group.
ImportantAfter you disable RTC, the RPO of the async replication pair is no longer guaranteed to be 10 minutes or less. Assess the impact carefully.
RTC monitoring metrics
Log on to the EBS console. In the top navigation bar, select the region where the target instance is located.
In the navigation pane on the left, choose .
Click the ID of the target async replication pair to go to its details page. In the Monitoring Information section, view the RTC monitoring metrics.
Metric
Description
Replication latency
This is the RPO. It indicates the time lag of the data on the secondary disk relative to the primary disk. The unit is seconds.
This value represents the time span of data that might be lost if a failure occurs. For example, an RPO of 300 seconds (5 minutes) means the data on the secondary disk is 5 minutes behind the data on the primary disk.
Amount of data pending replication
The total amount of data on the primary disk waiting to be replicated to the secondary disk at a specific point in time. The unit is bytes.
Billing
No extra fees are charged for enabling RTC for async replication pairs that replicate data between different zones in the same region.
If you enable RTC for a cross-region async replication pair, you are charged an additional fee based on the volume of replicated data. The unit price is 0.0143 USD/GB.