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

Change methods

You can upgrade or downgrade the configuration of an RDS PPAS 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.

Configuration items

If you want to horizontally scale the read capability of an RDS PPAS instance, you can create read-only instances. For more information, see Introduction to SQL Server read-only instances and Create an RDS SQL Server read-only instance.
Configuration item Description
Version Some versions can be upgraded to later versions, see:
Edition The Basic Edition can be upgraded to the High-availability Edition, see Upgrade from Basic Edition to High-availability Edition
CPU and Memory All SQL Server DB engine versions and editions support the CPU and memory change.
Capacity All SQL Server DB engine versions and editions allow you to increase storage capacity.
  • You cannot decrease the storage capacity of an RDS instance.
  • For information about the capacity range, see Primary instance types.
  • If the storage capacity range of the current specifications cannot meet your requirements, you can change the specifications.
Note Changing the preceding configuration does not change the endpoints of the RDS instance.


For more information, see Specification change fees.


Your Alibaba Cloud account does not have an unpaid renewal order.


  • When the new configuration is taking effect, the RDS instance may be disconnected for about 30 seconds and most operations related to databases, accounts, and networks cannot be performed. Therefore, we recommend that you change the configuration during off-peak hours or make sure that your application can automatically reconnect to the RDS instance.
  • If the RDS instance is in the Basic Edition (which has no slave node as hot backup), it becomes unavailable for a long time during the configuration change. Therefore, if you have high requirements for database availability, we recommend that you select an edition higher than the Basic Edition. For example, you can select the High-availability Edition.


  1. Log on to the RDS console.
  2. In the upper-left corner, select the region where the target RDS instance is located.选择地域
  3. Find the target RDS instance and click the instance ID.
  4. On the Basic information page, find the Configuration Information section and click Change Specifications.变成配置
  5. Optional. If the RDS instance uses the subscription billing method, click Next in the displayed dialog box.
  6. On the Change Specifications page, change the instance configuration. For more information, see Configuration items.
  7. Specify the time at which you want to change the configuration.
    • Switch Immediately After Data Migration: Change the configuration immediately after the data migration.
    • Switch Within Maintenance Window: Change the configuration during the maintenance window.
    Note To change the maintenance window, follow these steps:
    1. Click Modify.修改维护时间段
    2. In the Configuration Information section, select a maintenance window and click Save. 修改维护时间段
    3. Go back to the Change Specifications page, refresh the page, and change the configuration again.
  8. Select Terms of Service, Service Level Agreement, and Terms of Use and click Confirm.


  1. Can I change the zone and version of an RDS instance?

    You can change the zone and version of an RDS instance only when the instance runs the SQL Server 2008 R2 engine. You can migrate an RDS SQL Server instance across zones in the same region separately. Alternatively, you can change the zone of an RDS SQL Server instance when you upgrade the instance version from SQL Server 2008 R2 to SQL Server 2012/2016.

  2. Do I need to migrate data if I only want to expand the storage capacity of an RDS instance?

    Check whether the server where the RDS instance is located provides sufficient storage capacity for expansion. If yes, you do not need to migrate data and can directly expand the storage capacity. If no, you must migrate data to a server that provides sufficient storage capacity before you expand the storage capacity.