Scaling Storage Space

Scenarios

If the storage space is not enough for your workloads, you can scale up storage space of your DB instance.

A DB instance needs to preserve at least 15% of its capacity to work properly. The new minimum storage space required to make this instance available has been automatically calculated for you. You are advised to set alarm rules for the Storage Space Usage metric to learn about the storage usage in a timely manner.

Services are not interrupted during storage scale-up.

Constraints

**Table 1** Constraints
Phase	Constraints	Duration
Storage scale-up	The maximum allowed storage is 4,000 GB. There is no limit on the number of scale-ups. For primary/standby DB instances, scaling up the primary DB instance will cause the standby DB instance to also be scaled up. A DB instance cannot be deleted during scale-up. If you scale up the storage of a DB instance with disk encryption enabled, the new storage will still use the original key for encryption.	The scale-up takes 3 to 5 minutes.

Scaling the Storage Space of a DB Instance

Log in to the management console.
Click in the upper left corner of the page and choose Databases > Relational Database Service.
On the Instances page, locate the target DB instance and choose More > Scale Storage Space in the Operation column.

Or use either of the following methods:
- Click the instance name to go to the Overview page. In the Storage & Backup area, click Scale Storage Space.
On the displayed page, specify the new storage space and click Next.

You can increase or decrease the storage by at least 10 GB. Enter a value that is a multiple of 10. The instance supports a storage space range from 40 GB to 4,000 GB.
Confirm the information.
- If you need to modify your settings, click Previous.
- If you do not need to modify your settings, click Submit for a pay-per-use instance or click Pay Now for a yearly/monthly instance.
Check the result.

Scaling storage space takes 3-5 minutes. During this period, the status of the DB instance on the Instances page will be Scaling up. After a while, click the instance name and check that the new value for storage space appears on the Overview page.

Scaling the Storage Space of a Read Replica

Scaling the storage space of a read replica does not affect that of the primary DB instance. You can separately scale read replicas to meet service requirements. New storage space of read replicas after scaling must be greater than or equal to that of the primary DB instance.

Log in to the management console.
Click in the upper left corner of the page and choose Databases > Relational Database Service.
On the Instances page, locate the target DB instance and click in front of it. Locate the read replica to be scaled and choose More > Scale Storage Space in the Operation column.

Or use either of the following methods:
- Click the read replica name to go to the Overview page. In the Storage & Backup area, click Scale Storage Space.
On the displayed page, specify the new storage space and click Next.

The minimum start value of each scaling is 10 GB. A read replica can be scaled up or down only by a multiple of 10 GB. The allowed minimum and maximum storage spaces are 40 GB and 4,000 GB, respectively.
Confirm the information.
- If you need to modify your settings, click Previous.
- If you do not need to modify your settings, click Submit for a pay-per-use read replica or click Pay Now for a yearly/monthly read replica.
Check the result.

Scaling storage space takes 3-5 minutes. During this period, the status of the read replica on the Instances page will be Scaling up. After a while, click the read replica name and check the new storage space on the displayed Overview page to verify that the scaling is successful.