Scaling Up a Replica Set Instance

You can scale up the storage space of an instance, and the backup space increases accordingly.

If the purchased storage space exceeds 600 GB and the available storage space is 18 GB, the database will be set to the read-only state when the disk is full.
If the purchased storage space is less than or equal to 600 GB and the storage usage reaches 97%, the database is set to the read-only state.

In addition, you can set alarm rules for the storage space usage. For details, see Configuring Alarm Rules. For details about the causes and solutions of insufficient storage space, see High Storage Usage.

Precautions

Scaling is available when your account balance is sufficient.
Storage space can only be scaled up. It cannot be scaled down.
If you scale up a DB instance with disks encrypted, the expanded storage space will be encrypted using the original encryption key.
An instance cannot be scaled up if it is in any of the following statuses:
- Creating
- Changing instance class
- Adding node
- Deleting node
- Upgrading minor version
- Switchover in progress
During scaling, services will not be interrupted, and the storage type cannot be changed.

Pricing

A pay-per-use instance is still billed on an hourly basis after the instance is scaled up.

If you scale up a yearly/monthly instance, you will pay price difference or get a refund.

Procedure

Log in to the management console.
Click in the upper left corner and select a region and a project.
Click in the upper left corner of the page and choose Databases > Document Database Service.
On the Instances page, locate the replica set instance and choose More > Scale Storage Space in the Operation column.

Figure 1 Scale Storage Space

Alternatively, on the Instances page, click the name of the replica set instance. In the Storage Space area on the Basic Information page, click Scale.

Figure 2 Scale Storage Space
On the displayed page, specify the desired amount of space to be added and click Next.

Figure 3 Scale Storage Space

Select at least 10 GB each time you scale up the storage, and the storage size must be multiples of 10 GB. If a DB instance has fewer than 16 vCPUs, the maximum storage that can be scaled up to is 2,000 GB. For an instance of 16 vCPUs or more, the maximum storage that can be scaled up to is 4,000 GB.
On the displayed page, confirm the storage space.
- For yearly/monthly DB instances
  - If you need to modify your settings, click Previous to go back to the page for you to specify details.
  - If you do not need to modify your settings, click Submit to go to the payment page and complete the payment.
- For pay-per-use DB instances
  - If you need to modify your settings, click Previous to go back to the page for you to specify details.
  - If you do not need to modify the specifications, click Submit to scale up the storage space.
Check the results.
- This process takes about 3 to 5 minutes. The status of the DB instance in the instance list is Scaling up.
- In the upper right corner of the instance list, click to refresh the list. The instance status changes to Available.
- In the Storage Space area on the Basic Information page, check whether the scaling up is successful.