You can use an existing cluster or purchase a new cluster to quickly create a global database network (GDN). A GDN supports cross-region disaster recovery or active geo-redundancy. This topic describes how to create and delete a GDN.
Limits
Cluster versions
Database engine: PostgreSQL 14
Edition: Enterprise Edition
High-availability Mode: Single zone (with hot standby storage cluster disabled)
Supported regions
GDN is available in more than 10 regions worldwide, including the Chinese mainland, China (Hong Kong), and other regions outside the Chinese mainland.
Primary Cluster Region | Secondary Cluster Region |
All regions in the Chinese mainland | In the same region as the primary cluster or in a region in the Chinese mainland other than the region where the primary cluster is located. The same region as the primary cluster, or any other region in the Chinese mainland. For example, if the primary cluster is in China (Hangzhou), the secondary cluster can be in China (Hangzhou) or any other region in the Chinese mainland. Note If you have other region requirements, submit a ticket to contact us. |
Regions outside the Chinese mainland | China (Hong Kong), Japan (Tokyo), South Korea (Seoul), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Thailand (Bangkok), Germany (Frankfurt), US (Silicon Valley), US (Virginia), and UK (London). |
For regions outside the Chinese mainland, you must sign the Cross-Border Data Transfer Compliance Agreement before you create a secondary cluster.
Feature limits
Clusters in a GDN do not support the serverless feature or In-Memory Column Index (IMCI).
Clusters in a GDN do not support the database and table restoration feature.
Other limits
A GDN can consist of one primary cluster and up to four secondary clusters.
The primary cluster and secondary clusters must have the same database engine version: PostgreSQL 14.
The node specifications of a secondary cluster must be greater than or equal to those of the primary cluster. We recommend that you keep the specifications consistent.
A cluster can belong to only one GDN.
Billing
Cross-region data transmission for a GDN is free of charge. You need to pay only for the PolarDB clusters.
Create a global database network
Log on to the PolarDB console. In the navigation pane on the left, click Global Database Network (GDN).
On the Global Database Network (GDN) page, click Create Global Database Network.
In the Create Global Database Network (GDN) dialog box, configure the following parameters.
Parameter
Description
Compatibility
Select PostgreSQL.
Version
The value is fixed to Single-active Version.
Name
The name of the GDN. We recommend that you specify a business-friendly name for easy identification. The name does not need to be unique.
Primary Region
Select the region where the primary cluster resides.
NoteFirst, determine which cluster to use as the primary cluster, and then select the region of that cluster.
Primary Cluster
Select an existing cluster as the primary cluster of the GDN.
Global Domain Name
This feature is not currently supported. Keep it disabled.
Click OK. You can view the created GDN on the Global Database Network (GDN) page. You can then add a secondary cluster to the GDN.
Delete a global database network
You can delete a GDN only if it contains only the primary cluster.
A deleted GDN cannot be recovered. Proceed with caution.
After you delete a GDN, applications connected to it can no longer access the database. You must promptly update the connection code in your applications.
Log on to the PolarDB console. In the navigation pane on the left, click Global Database Network (GDN).
On the Global Database Network (GDN) page, find the target GDN and click Delete in the Actions column.
NoteIf the Delete button is grayed out, this indicates that the GDN contains secondary clusters. You must delete the secondary clusters before you can delete the GDN.
Read the notes in the dialog box. After you confirm the information, click OK to delete the GDN.
References
Global Database Network (GDN): Describes GDN, its service architecture, and common scenarios.
Add and manage a secondary cluster: Describes how to add a secondary cluster to a GDN.
Connect to a global database network: Describes how to connect to a GDN.
Related API operations
API | Description |
Creates a global database network. | |
Deletes a global database network. | |
Queries the information of a specific global database network. | |
Queries the information of all global database networks. | |
Modifies the information of a global database network. |