PolarDB for PostgreSQL clusters provide the network channel feature. You can use network channels to access data in other databases by using different methods such as Foreign Data Wrapper (FDW) external tables, dblink. This topic describes how to create a network channel from a PolarDB for PostgreSQL cluster to a self-managed database built on an ECS instance.
Prerequisites
Only clusters that run PolarDB for PostgreSQL 14 or earlier database engines support this feature.
The ECS-hosted self-managed database must be a PostgreSQL or Oracle database.
The ECS instance is deployed in a virtual private cloud (VPC).
The PolarDB for PostgreSQL cluster and the ECS-hosted self-managed database are created and managed by using the same Alibaba Cloud account.
The PolarDB for PostgreSQL cluster and the ECS-hosted self-managed database are in the same region.
The edition of the PolarDB for PostgreSQL cluster is Enterprise Edition.
Usage notes
You can create up to three network channels for a PolarDB for PostgreSQL cluster in a region.
Procedure
Log on to the PolarDB console. Click Clusters in the left-side navigation pane. Select a region in the upper-left corner and click the ID of the cluster in the list to go to the Basic Information page.
In the left-side navigation pane, choose Settings and Management > Databases.
On the Databases page, click the Network Channels tab.
Select Network Channels to Self-managed Databases.
Click Create Network Channels to Self-managed Databases and configure the parameters. The following table describes the parameters.
Parameter
Description
Channel Name
The name of the network channel. The name must meet the following requirements:
The name must contain lowercase letters and can contain digits and underscores (_).
The name starts and ends with a lowercase letter or a digit.
The name can be up to 64 characters in length.
This name is required when you use cross-database queries.
Source Instance Name
The name of the current PolarDB for PostgreSQL cluster. The value is fixed and cannot be modified.
Region of Destination Instance
The ID of the region in which the ECS instance resides, such as cn-hangzhou.
The value is fixed to the region in which the current PolarDB for PostgreSQL cluster resides.
You can view the zone in which the ECS instance resides in the ECS console or view the ID of the region in which the ECS instance resides by calling the DescribeInstances API.
VPC of Destination Instance
The VPC in which the ECS instance resides.
To view the VPC ID of the destination ECS instance, log on to the ECS console, and go to the Instance Details page of the ECS instance. You can find the VPC ID of the ECS instance in the Configuration Information section.
VPC ID of Destination Instance
The IP address of the ECS instance.
To view the primary private IP address of the destination ECS instance, log on to the ECS console, and go to the Instance Details page of the ECS instance. You can find the primary private IP address of the ECS instance in the Configuration Information section.
VPC Port of Destination Instance
The port number of the self-managed database hosted on the ECS instance.
Remarks
The remarks for the network channel.
Click OK.