You can enable autoscaling for GeminiDB Cassandra instances. When storage usage reaches the limit, autoscaling is triggered.

You can enable autoscaling:

When creating an instance

For details, see Creating a GeminiDB Cassandra Instance.
After creating an instance

For details, see operations in this section.

If you enable autoscaling as a domain user, no additional configuration is required.
If you enable autoscaling as an IAM user first time, you need to temporarily assign the permission of creating an agency to the user.

Permission Configuration

If you are using an IAM user, configure the following permissions before enabling autoscaling:

GeminiDB FullAccess

IAM fine-grained permission

For details, see Creating a Custom Policy.

Custom policy in JSON format:

{
     "Version":"1.1",
     "Statement":[
         {
             "Effect":"Allow",
             "Action":[
                 "iam:permissions:listRolesForAgencyOnProject",
                 "iam:permissions:grantRoleToGroupOnProject",
                 "iam:agencies:createAgency",
                 "iam:agencies:listAgencies",
                 "iam:roles:listRoles",
                 "iam:roles:createRole"
             ]
         }
     ]
}

Creating a User Group and Assigning Permissions
You can create a user group on the IAM console and assign it custom permissions created in 2 and system role Security Administrator.
Adding Users to or Removing Users from a User Group
Log in to the IAM console as a domain or an IAM user. Locate the IAM user that the target instance belongs to and add it to the user group created in 3. The IAM user will inherit permissions of the user group.

Precautions

The instance is in the Available status.
Once autoscaling is enabled, an agency will be created and fees will be automatically deducted.

Automatically Scaling Up Storage of a Single Instance

Log in to the GeminiDB console by following Logging In to the GeminiDB Console.
On the Instances page, click the instance. The Basic Information page is displayed.
In the Storage Space area, click Auto Scale.
Figure 1 Auto Scale

Toggle on Auto Scale and specify the parameters below.

Figure 2 Configuring autoscaling

**Table 1** Parameter description
Parameter	Description
Auto Scale	If you toggle on this switch, autoscaling is enabled.
Trigger If Available Storage Drops To	When the available storage usage drops to this value or the available storage space drops to 10 GB, autoscaling is triggered.
Increase By	Percentage of the current storage to be automatically scaled. The value can be 10, 15, or 20. If the value is not a multiple of 10, the value is rounded up. At least 100 GB is added each time.
Storage Limit	Limit of storage (GB) that can be automatically scaled to. The value must be no less than the current storage of your instance and cannot exceed the storage space upper limit defined by your instance specifications.

Click OK.

Automatically Scaling Up Storage of Multiple Instances In Batches

Log in to the GeminiDB console by following Logging In to the GeminiDB Console.
Select instances and click Auto Scale.
Figure 3 Auto Scale

Select an instance, toggle on Auto Scale, and specify the parameters below.

Figure 4 Batch Auto Scale

**Table 2** Parameter description
Parameter	Description
Auto Scale	If you toggle on this switch, autoscaling is enabled.
Trigger If Available Storage Drops To	When the available storage usage drops to this value or the available storage space drops to 10 GB, autoscaling is triggered.
Increase By	Percentage of the current storage to be automatically scaled. The value can be 10, 15, or 20. If the value is not a multiple of 10, the value is rounded up. At least 100 GB is added each time.
Storage Limit	This parameter cannot be customized. By default, the storage is scaled up the maximum of the selected instance.

Click OK.

Configuring Auto Scale

Permission Configuration

Precautions

Automatically Scaling Up Storage of a Single Instance

Automatically Scaling Up Storage of Multiple Instances In Batches