Change configuration for ApsaraDB RDS for MySQL - ApsaraDB RDS

Change the configuration of an ApsaraDB RDS for MySQL instance, including the instance edition, instance type upgrades or downgrades, and storage space scaling.

For all supported configuration changes, see Instance configuration changes.

For other database engines, see:

Prerequisites

The instance uses the subscription or pay-as-you-go billing method.

Note
If the instance uses the serverless billing method, see Configure a serverless instance.
Your Alibaba Cloud account has no unpaid renewal orders.
The instance is in the Running state. If your instance is locked, unlock the instance before you change the configuration.

Limitations

Order limit: After you submit a configuration change order, you cannot cancel it. Carefully evaluate your business requirements before you change the configuration.
Limits on read-only instances:
- When you change the configuration of a read-only instance, its primary instance must be in the Running state.
- The storage space of a read-only instance must be greater than or equal to the current storage space of its primary instance. We recommend that you first scale out the storage of all read-only instances before you scale out the storage of the primary instance.
Limits on scaling in storage space:
- Scale-in for instances that use a local disk with enhanced performance
  - After a scale-in, the new storage space must be at least 120% of the used storage space.
    
    Example: An instance has 100 GB of storage space, of which 50 GB is used. After a scale-in, at least 60 GB (50 GB × 120%) of storage space must be retained.
- General scale-in limits
  - Basic Edition or High-availability Edition: You can scale in the storage space only for instances with the same edition and architecture.
  - The minimum storage space after a scale-in is calculated using the following formula: min{current usage × 1.3, current usage + 400 GB}. The result must be at least the minimum storage space supported by the current instance type.
  - Step size: The storage space can be adjusted in 5 GB increments.
  - If binary logs (binlogs) are rapidly generated on the instance, you must retain a sufficient number of logs on the local disk before scaling in the instance's storage space. For information about how to enable log backup, see Modify the backup policy for an ApsaraDB RDS instance.
Limits on product type changes:
- Zone compatibility: Compared with the standard edition, Yitian Edition supports fewer zones. If you cannot change the product type due to zone limits, first change the zone of the instance and then change the product type.
- Minor engine version constraints: The new minor engine version must be the same as or later than the current version. You cannot downgrade the minor engine version.
- Edition constraints: For Basic Edition instances, you can change the product type only from Yitian Edition to the standard edition. For High-availability and Cluster Edition instances, you can switch the product type between Yitian Edition and the standard edition.
Limits on legacy instance types: You cannot directly change the configuration of a legacy instance. You must first upgrade the instance to a current instance type that is publicly available. Then, you can change its configuration.
Other limits: You can change only the items that are listed in Instance configuration changes.

Impacts

Instance storage type	Configuration item	Impacts
Instances that use a local disk with enhanced performance	Instance type, instance edition, or storage space	Changing the instance type or instance edition when no local resources are available triggers automatic data migration. After migration, a switchover occurs at your specified time. Incremental data is synchronized during migration. Important A configuration change triggers an instance switchover, which typically causes a transient connection that lasts for about 15 seconds. The actual duration may be longer if the client is not properly configured or uses an outdated driver version. We recommend that you perform the change during off-peak hours and ensure that your application has an automatic reconnection mechanism. During an instance switchover, most database, account, and network operations cannot be performed. For more information, see Impacts of an instance switchover.
Instances that use a cloud disk	Instance type or instance edition	The configuration change takes several minutes regardless of the data volume. Important A configuration change triggers an instance switchover, which typically causes a transient connection that lasts for about 15 seconds. The actual duration may be longer if the client is not properly configured or uses an outdated driver version. We recommend that you perform the change during off-peak hours and ensure that your application has an automatic reconnection mechanism. During an instance switchover, most database, account, and network operations cannot be performed. For more information, see Impacts of an instance switchover.
Instances that use a cloud disk	Storage space	When you scale out storage: A transient connection occurs if the instance uses a standard SSD. No transient connection occurs if the instance uses an ESSD or a high-performance cloud disk. When you scale in storage: A transient connection occurs. For more information, see Scale in the storage space of a cloud disk (Scale-in is not supported for standard SSDs). Note If a snapshot is being created for a cloud disk, tasks to scale out the disk or change its performance level will run only after the snapshot is complete.

Note

You do not need to restart the instance after a configuration change. Stored data is not lost.
The instance ID and endpoint remain unchanged. However, if the instance is migrated across hosts, the IP address of the endpoint changes. We recommend using the endpoint, not the IP address, to connect to the database.

Billing

For more information, see Billing rules for configuration changes.

Procedure

Important

After you submit a configuration change order, you cannot cancel it. Carefully evaluate your business requirements before you proceed.

Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the Configuration Information section, click Change Specifications.
(This step is required only for subscription instances.) In the dialog box that appears, select a change method and click Next.

The following change methods are available:

Upgrade or Downgrade: The new configuration takes effect immediately. Both subscription and pay-as-you-go instances support these options.

After you submit the configuration change task, the system reassigns the original instance ID and endpoint to a new instance, so both remain unchanged.
Modify the instance configuration.
Note
- All instance types support instance type and storage space changes. For legacy instance types, you must first upgrade the instance to a current instance type that is publicly available before you can scale out its storage space.
- You can scale in storage space for High-availability Edition instances that use a local disk with enhanced performance, and Basic or High-availability Edition instances that use a cloud disk (excluding standard SSDs). Other instance types do not support storage scale-in.
- You can change the instance edition of an ApsaraDB RDS for MySQL 5.6 three-node Enterprise Edition instance to High-availability Edition.
- You can upgrade an ApsaraDB RDS for MySQL 5.7 Basic Edition instance to a High-availability Edition instance that uses a local disk with enhanced performance.
- For ApsaraDB RDS for MySQL 8.0 or 5.7 High-availability Edition instances that use ESSDs, you can change the instance edition to Cluster Edition.
- On the Change Specifications page, the instance type defaults to Current Type. Verify that the new instance type's parameters meet your requirements before proceeding.
Select a Switch Time.
- Execute Immediately: The switchover occurs immediately after data migration is complete.
- Switch Within Maintenance Window: The switchover occurs within the specified maintenance window.
Important
- If you select Switch Within Maintenance Window, the instance remains in the Upgrading or Downgrading state until the switchover is complete. During this period, you cannot perform instance-level operations, such as configuration changes, version upgrades, or cross-zone migrations on the instance.
- If you only scale out storage space or change the storage type to ESSD, the change typically has no impact on your services and takes effect immediately. You do not need to select Switch Within Maintenance Window.
- A Basic Edition instance has only one database node and does not have a secondary node for hot backup. Therefore, a long service interruption occurs when you change the configuration of the node. We recommend that you change the configuration during off-peak hours to minimize the impact on your business.
- For instances other than Basic Edition, one or two instance switchovers may occur when the configuration change takes effect. Although this does not affect normal use, we recommend that you change the configuration during off-peak hours or make sure that your application has an automatic reconnection mechanism. For more information about the impacts of an instance switchover, see Impacts of an instance switchover.
On the Change Specifications page, confirm the specifications of the instance before and after the change, click Confirm Order, and then complete the payment.
Warning
- After you submit a configuration change order, you cannot cancel it. We recommend that you carefully evaluate your business requirements before you proceed.
- To ensure a successful configuration change, do not perform any Data Definition Language (DDL) operations from the time you submit the order until the change is complete.

FAQ

Disk scale-out and scale-in

Q: Why is my instance still locked after I scaled out its storage?

A: An instance locked due to full storage is automatically unlocked after the scale-out task completes. On the Basic Information page of the instance, click the icon in the upper-right corner to open the Task List page and view the task progress.
Q: Why does a transient connection occur when I scale out the storage space?

A: Storage scale-out requires an instance switchover. For more information, see Impacts of an instance switchover.
Q: Is the free backup quota increased after I scale out the storage?

A: Yes. For more information, see Free backup quota.

Storage type change

Q: How do I change the storage type (local disk with enhanced performance, standard SSD, or ESSD)?

A: See Change the storage type from cloud disk to local disk with enhanced performance.
Q: How do I enable automatic storage expansion for an instance that uses a local disk with enhanced performance?

A: You can change the storage type from local disk with enhanced performance to cloud disk and then enable automatic storage expansion. Alternatively, you can purchase a new instance with a cloud disk and migrate your data to it.
Q: The storage space of my ApsaraDB RDS for MySQL instance that uses a local disk with enhanced performance has reached its upper limit. How can I increase the storage space?

A: For more information about the storage space range of an ApsaraDB RDS for MySQL 8.0 or 5.7 instance on High-availability Edition that uses a local disk with enhanced performance, see ApsaraDB RDS for MySQL High-availability Edition (with a local disk). To increase the storage space, you can change the storage type from a local disk with enhanced performance to a cloud disk to obtain a larger storage capacity.

Storage space management

Q: What do I do if an "insufficient inventory" error is reported when I try to upgrade the storage space?

A: We recommend that you migrate the instance to another zone and then scale out the storage. After migration, the endpoint remains unchanged, but the corresponding IP address changes. Configure an automatic reconnection mechanism for your application.
Q: If I only scale out the storage space, do I need to migrate data to a new instance?

A: In most cases, scaling out storage on a cloud disk instance (non-Basic Edition) causes no transient connection. For instances that use a local disk with enhanced performance, one of the following situations occurs:
- The host has sufficient storage: Storage is directly scaled out with no impact on the instance.
- The host has insufficient storage: New primary and secondary instances are automatically created, and data is synchronized. A transient connection lasting about 15 seconds occurs during the switchover.
Note
You cannot query the remaining storage space of the host where the instance is deployed.
Q: If I delete a database from an ApsaraDB RDS for MySQL instance, is the disk space released?

A: The DROP statement releases disk space. The DELETE statement creates fragments and does not release disk space.

Impacts of configuration upgrades

Q: If I upgrade the CPU, memory, and disk at the same time, how long will my service be unavailable?

A: The service is unavailable for several minutes regardless of whether you upgrade a single item or multiple items. During the upgrade, an instance switchover or restart may occur, and most database, account, and network operations cannot be performed. We recommend that you perform configuration changes within the maintenance window. For more information, see Impacts of configuration changes.
Q: What factors affect the duration of a configuration change?

A: See What factors affect the duration of a configuration change for an ApsaraDB RDS for MySQL instance?.
Q: Does a configuration change affect online services?

A: See the Impacts section in this topic.

Read-only instances

Q: If I upgrade the primary instance, are the read-only instances also upgraded?

A: No. You must upgrade the read-only instances' configuration manually.
Q: Does scaling out the storage of the primary instance affect data replication to its read-only instances?

A: No.

Connections and network

Q: Does the endpoint change after a configuration change?

A: The endpoint (for example, rm-bpxxxxx.mysql.rds.aliyuncs.com) remains unchanged, but the corresponding IP address may change. We recommend using the endpoint instead of the IP address in your application.
Q: How do I configure an automatic reconnection mechanism for my application?

A: For Java applications, we recommend setting the time to live (TTL) to 60 seconds or less. This ensures that when the virtual IP (VIP) address of the endpoint changes, the application re-queries DNS to get and use the new VIP address. For more information about how to set the TTL in Java, see the official JDK documentation.

Instance types and billing

Q: Can I change a regular instance to a serverless instance?

A: No. To use a serverless instance, you must create one. For more information, see Create a serverless instance.
Q: How am I charged for automatic storage expansion?

A: Automatic storage expansion is disabled by default and is free to enable. When triggered, it is charged the same as manual expansion. For more information, see Change configuration.
Q: I mistakenly downgraded an instance and then immediately upgraded it back to the original configuration. Why is the difference between the refund and the fee so large?

A: The instance may have been purchased with a discount. When you upgrade again, the discount may no longer apply, and the price increases.

Automatic expansion and scale-in

Q: What are the rules for automatic storage expansion?

A: For more information, see Enable automatic storage expansion.
Q: What are the impacts of scaling in the storage space of an instance that uses a cloud disk?

A: A transient connection occurs when you scale in the storage space of an instance that uses a cloud disk. For more information, see Scale in the storage space of an instance that uses a cloud disk.
Q: Can I scale in an instance that uses a local disk with enhanced performance?

A: Yes. While the instance is running, click Change Specifications and then select Downgrade.

Zone migration

Q: How do I change a single-zone deployment to a multi-zone deployment?

A: For more information, see Migrate an instance across zones.

API reference

API	Description
ModifyDBInstanceSpec	Changes the configuration of an ApsaraDB RDS instance.