ApsaraDB RDS:Global Active Database

Overview

ApsaraDB RDS for PostgreSQL provides disaster recovery through Global Active Database (GAD). GAD uses native physical replication and Data Transmission Service (DTS) in a primary-secondary architecture to deliver cost-effective geo-disaster recovery with real-time data synchronization and nearby access.

Solution architecture

Scenarios

GAD supports the following use cases:

• Geo-disaster recovery

  Your business requires cross-region high availability and a low recovery time objective (RTO) to protect against region-level failures.

• Cross-region read-only instances

  Your business needs to perform cross-region queries and requires low-latency read access.

Benefits

• Secure and reliable

  • Built on native RDS PostgreSQL physical replication for efficient, stable performance without compatibility issues.

  • Both RDS and DTS are backed by strict SLAs for database availability and synchronization link security.

• Easy to use

  • The RDS console provides a configuration interface to quickly set up GAD disaster recovery.

  • Built-in disaster recovery assessment, one-click switchover, and latency monitoring cover the full disaster recovery lifecycle.

• Cost-effective

  • Use cost-effective RDS instance families such as Yitian and Basic series for disaster recovery instances.

  • DTS manages the GAD network link with a serverless architecture that auto-scales bandwidth. You pay based on actual usage.

Limitations

Billing

GAD costs include RDS instance fees and DTS data synchronization fees. If you use an existing instance to create an instance group or add a secondary instance, you are charged only for data synchronization.

• New ApsaraDB RDS instance fees

  When you purchase a new RDS PostgreSQL instance for an instance group or secondary instance, charges include instance type fees and storage fees. Both subscription and pay-as-you-go billing methods are supported.

• Data synchronization fees

  When you add a secondary instance to an instance group, the system automatically creates a one-way data synchronization link between the primary and secondary instances. Charges depend on region, link type, number of links, and usage duration.

  Data synchronization fee = Unit price per data synchronization link × Number of links × Usage duration

  The unit price for a one-way synchronization link is: USD 0.187969924812/hour/link

Get started

• Method 1: Purchase a new RDS PostgreSQL instance and add it as a GAD secondary instance

  1. Create a GAD instance group.

  2. Create a new RDS PostgreSQL instance and add it as a secondary instance to the GAD instance group. Method 1: Create a new instance and add it as a secondary instance.

• Method 2: Add an existing RDS PostgreSQL instance as a GAD secondary instance

  1. Create a GAD instance group.

  2. Add an existing RDS PostgreSQL instance as a secondary instance to the GAD instance group. Method 2: Add an existing instance as a secondary instance.

• Method 3: Create a GAD from the Disaster Recovery Instance section on the Basic Information page of the instance

  1. Go to the Basic Information page of the source RDS instance. In the Disaster Recovery Instance section, create a GAD instance group.

  2. Create a new RDS PostgreSQL instance or add an existing one as a secondary instance to the GAD instance group. Method 1: Create a new instance and add it as a secondary instance or Method 2: Add an existing instance as a secondary instance.