Overview

Scenarios

You can create a cross-region DR relationship for your DB instance. If the production instance fails or the service system breaks down due to other force majeure factors, the DR instance in another region ensures that the production data is not lost and the production system runs uninterruptedly. This improves the system availability.

This practice includes the following tasks:

• Create an RDS for PostgreSQL instance.
• Create a cross-region DR relationship for the RDS for PostgreSQL instance.

Prerequisites

• You have registered with Huawei Cloud and completed real-name authentication.
• Your account balance is greater than or equal to $0 USD.

Constraints

• The primary DB instance and DR instance must be available and are deployed in different clouds or regions. The primary DB instance is deployed in primary/standby mode and the DR instance is deployed in standalone mode.
• The DR instance cannot be configured for DR until the primary DB instance is configured.
• The specifications of the DR instance are at least equal to those of the primary DB instance.
• Cross-cloud or cross-region DR is supported only for RDS for PostgreSQL 12 and later versions.
• Cross-cloud or cross-region DR relationships cannot be established across major versions.
• The DR instance can be promoted to primary and the DR replication status can be queried only after the DR relationship between the primary DB instance and DR instance is established.
• Ensure that the primary DB instance and DR instance are in the regions where Cloud Connect or Virtual Private Network (VPN) has been rolled out.
• DR instances do not support point-in-time recovery (PITR) or CBR snapshot-based backups. Perform such operations on the primary instance if needed.

How Cross-Region DR Works

Two RDS for PostgreSQL instances are deployed in two data centers, one in the production center and the other in the DR center. RDS replicates data from the primary instance in the production center to the DR instance in the DR center, keeping data synchronous across the regions. Before using this function, ensure that Cloud Connect can be used to connect the two regions.

Figure 1 Diagram

Service List

• Cloud Connect
• Virtual Private Cloud (VPC)
• Relational Database Service (RDS)

Notes on Usage

• The resource planning in this practice is for demonstration only. Adjust it as needed.
• The end-to-end test data in this practice is for reference only.