Scaling up Storage Space

Scenarios

If the original storage space is insufficient as your services grow, you can scale up storage space of your DB instance.

When the storage usage is greater than or equal to 97%, the DB instance status changes to Storage full. Your connection to the instance is intermittently interrupted and the instance becomes read-only. When this happens, data cannot be written to the 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. For details, see Setting Alarm Rules.

During the scale-up period, services are not interrupted.

Constraints

• You can scale up storage space only when your account balance is greater than or equal to $0 USD.
• 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 accordingly.
• The instance cannot be deleted during scaling.
• Storage space can only be scaled up.
• If you scale up a DB instance with the disk encrypted, the expanded storage space will be encrypted using the original encryption key.

Billing

Scaling up a Primary DB Instance

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

   You can also perform the following operations to scale up storage space:

   • Click the target DB instance to enter the Basic Information page. In the Storage Space area, click Scale.
   • If the storage space is full, locate the target DB instance on the Instances page and click Scale in the Status column.

5. On the displayed page, specify the new storage space and click Next.

   The minimum start value of each scaling is 10 GB. A DB instance can be scaled up only by a multiple of 10 GB. The allowed maximum storage space is 4,000 GB.

   The maximum storage space depends on the DB engine and instance specifications.

6. Confirm specifications.
   • If you need to modify your settings, click Previous.
   • If you do not need to modify the settings, click Submit for a pay-per-use instance or click Pay Now for a yearly/monthly instance.

7. View the scale-up result.

   Scaling up storage space takes 3-5 minutes. During this time period, the status of the DB instance on the Instances page will be Scaling up. After a while, click the DB instance and view the new storage space on the displayed Basic Information page to verify that the scale-up is successful.

Scaling up a Read Replica

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

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click in the upper left corner of the page and choose Databases > Relational Database Service.
4. 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.

   You can also perform the following operations to scale up storage space:

   • Click the read replica to enter the Basic Information page. In the Storage Space area, click Scale.
   • If the storage space is full, locate the read replica on the Instances page and click Scale in the Status column.

5. 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 only by a multiple of 10 GB. The allowed maximum storage space is 4,000 GB.

   The maximum storage space depends on the DB engine and instance specifications.

6. Confirm specifications.
   • If you need to modify your settings, click Previous.
   • If you do not need to modify the settings, click Submit for a pay-per-use instance or click Pay Now for a yearly/monthly instance.

7. View the scale-up result.

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