This topic describes how to change the specifications of an ApsaraDB RDS for PostgreSQL instance. These specifications include the instance type and the storage capacity.

Prerequisites

Your Alibaba Cloud account does not have overdue renewal orders.

Change items

You can create read-only RDS instances to scale the read capability of your database system. These instances can offload queries from the primary RDS instance. For more information, see Introduction to RDS PostgreSQL read-only instances and Create an RDS PostgreSQL read-only instance.

Change item Description
Instance type

You can change the instance types of all RDS instances.

Storage capacity

You can increase the storage capacity of all RDS instances.

If an RDS instance uses subscription billing and local SSDs, you can decrease the storage capacity only when you select the change upon renewal method. For more information, see Subscription renewal.

Note
  • The new storage capacity that you specify for an RDS instance must fall within the storage capacity range that is allowed for the instance type. For more information, see Primary instance types.
  • If an RDS instance uses standard or enhanced SSDs, you cannot decrease its storage capacity.
  • If the storage capacity range that is allowed for the instance type does not meet your business requirements, we recommend that you select another instance type.
Note Changing the preceding specifications of an RDS instance does not incur changes to the endpoints of the RDS instance.

Billing

For more information, see Specification change fees.

Precautions

  • Data may be migrated after you change the specifications of an RDS instance. After the migration is complete, the RDS instance switches over services during the scheduled time period. The switchover does not interrupt the synchronization of incremental data. During a switchover, a 30-second brief disconnection may occur. In addition, operations related to databases, accounts, and networks cannot be performed. We recommend that you change the specifications during off-peak hours or make sure that your application is configured to automatically reconnect to your RDS instance.
  • After you change the specifications of an RDS instance, you do not need to manually restart the RDS instance.
  • In the RDS Basic Edition, the database system consists of only one primary RDS instance, and no secondary RDS instances are provided as hot backups. If the primary RDS instance breaks down, is undergoing specification changes, or is upgrading, it becomes unavailable until the operations are done. If you require high database availability, we recommend that you use the RDS High-availability, Cluster, or Enterprise Edition.

Procedure in the ApsaraDB for RDS console

  1. Log on to the ApsaraDB for RDS console.
  2. In the left-side navigation pane, click Instances. In the top navigation bar, select the region where the target RDS instance resides.
    Select a region
  3. Find the target instance and click the instance ID.
  4. Click Change Specifications.
  5. In the dialog box that appears, select a change method and click Next. This step is required only for subscription instances.
    Note You can select Upgrade or Downgrade for both subscription and pay-as-you-go instances. The new specifications immediately take effect.
  6. Change the specifications of the RDS instance. For more information, see Change items.
  7. Specify the Switching Time.
    • Switch Immediately After Data Migration: The system executes the specification changes immediately after data migration is complete.
    • Switch Within Maintenance Window: The system executes the specification changes during the maintenance window that you specify. While the specification changes are taking effect, a brief disconnection of about 30 seconds may occur. This disconnection interrupts most of the operations related to databases, accounts, and network settings. Therefore, we recommend that you select this option.
  8. On the Change Specifications page, read and select Terms of Service, and click Pay Now.

FAQ

  1. How do I change the storage type of my RDS instance that is equipped with local, standard, or enhanced SSDs?

    For more information, see How to change a cloud disk to a local disk.

  2. If I only want to increase the storage capacity of an RDS instance, do I need to migrate the data to a new instance?

    Check whether the host where the RDS instance resides can provide sufficient storage capacity. If yes, the system increases the storage capacity without migrating data. If no, the system migrates the data to a new RDS instance before increasing the storage capacity. The new RDS instance must reside on a host that can provide sufficient storage capacity.

Related operations

Operation Description
ModifyDBInstanceSpec Changes the specifications of an RDS instance.