This topic describes how to change the configuration of an RDS for PostgreSQL instance, including the edition, specifications, storage capacity, storage class, and zone.

You can upgrade or downgrade the configuration of an RDS for PostgreSQL instance at any time regardless of whether the instance uses the subscription or pay-as-you-go billing method. The new configuration takes effect immediately after you complete the configuration upgrade or downgrade.

Change items

If you want to increase the read capability of a database, you can create read-only instances to relieve the pressure. For more information, see Introduction to RDS for PostgreSQL read-only instances and Create an RDS for PostgreSQL read-only instance.

Change item Description
Instance type

You can modify the specifications of all instance types.

Capacity

You can increase the storage capacities of all instances.

You can decrease the storage capacity of subscription-based instances that are deployed based on local disks by using the renewal method.

Note
  • You cannot specify a storage capacity that exceeds the storage capacity limit of the instance type. For more information, see Instance types.
  • You cannot decrease the storage capacities of instances that are deployed based on cloud disks.
  • If the storage capacity of the instance type cannot meet your needs, we recommend that you use a different instance type.
Note Changing the above specifications does not change the endpoint of the instance.

Billing rules

For more information, see Billing details about configuration change.

Prerequisites

Your Alibaba Cloud account does not have overdue renewal orders.

Precautions

  • Your RDS instance may be disconnected for about 30 seconds when the specification changes take effect. During this period, management operations related to databases, accounts, and networks cannot be performed. We recommend that you change the specifications during off-peak hours, or configure automatic reconnection policies for your applications.
  • In the Basic Edition, your RDS instance is not attached with any slave instances that can serve as hot backups. Therefore, if your RDS instance breaks down unexpectedly or you are changing the instance configuration or upgrading the instance version, your RDS service may remain unavailable for a long period of time. If you have high availability requirements on databases, we recommend that you use other editions such as the High-availability Edition.

Procedure

  1. Log on to the RDS console.
  2. Select the target region.Select a region
  3. Find the target RDS instance and click the instance ID.
  4. On the Basic Information page that appears, click Change Specifications in the Configuration Information section.Configuration Information
  5. In the dialog box that appears, select the change method and click Next. This step is only required for subscription-based instances.Select a configuration change method
  6. Modify Type and Capacity.
  7. Specify the time to change the instance specifications.
    • Switch Immediately After Data Migration: Changing the instance specifications involves underlying data migration. You can change the configuration after data migration.
    • Switch Within Maintenance Window: Your RDS instance may be disconnected for about 30 seconds when the specification changes take effect. During this period, management operations related to databases, accounts, and networks cannot be performed. We recommend that you change the configuration within the maintenance window.
      Note If you want to change the maintenance window, following these steps:
      1. Click Modify.Change the maintenance window
      2. In the Configuration Information section, change the maintenance window and click Save.Configuration Information - Change the maintenance window
      3. Return to the configuration change page, refresh the page, and change the configuration.
  8. On the Change Specifications page, select the Product Terms of Service, click Confirm, and complete the payment.

FAQ

Do I need to migrate data to a new instance if I only expand the capacity?

Check whether there is sufficient storage space on the host where the instance is located for upgrading. If yes, you can upgrade without migrating data. If no, you must migrate data to a host that has enough storage space.

APIs

API Description
ModifyDBInstanceSpec Modifies the specifications of an RDS instance.