Configuring Auto Scale

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

You can enable storage autoscaling when or after creating an instance. For details, see Buying an Instance.

This section describes how to configure Auto Scale after an instance is created.

Configuring Permissions

If you are an IAM user, perform the following operations to configure GeminiDB permissions and IAM permissions before you enable storage autoscaling:

Configure fine-grained permissions for IAM and minimum permissions for GeminiDB.

For details about how to configure IAM permissions, see Creating a Custom Policy.

{
     "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"
             ]
         }
     ]
 }

Create a user group and assign permissions to it.
You can create a user group on the IAM console and grant it custom permissions created in 1 and the security administrator role.
Add a user to a user group.
Log in to the IAM console using a Huawei Cloud account or an IAM account, locate the IAM user that the target instance belongs to, and add it to the user group created in 2. The IAM user will inherit permissions of the user group.

Precautions

Autoscaling is available only when your account balance is sufficient.
Autoscaling is currently in open beta testing. If you need to use this function, contact customer service to apply for it.
The instance is in the Available status.
Once autoscaling is enabled, an agency will be created and fees will be automatically deducted.
Only general-purpose GeminiDB Redis instances are supported.
When the storage usage is greater than 98%:
- If the total storage is less than 600 GB, the storage usage after autoscaling (used storage space/total storage space) will be less than 85%. For example, if the total storage is 500 GB and the used storage space is 495 GB, the storage usage (495/total storage space) after autoscaling will be less than 85%.
- If the total storage is greater than or equal to 600 GB, the system automatically scales up the storage by over 90 GB. For example, if the total storage is 700 GB, the storage after autoscaling will be greater than 790 GB (700 + 90).
Changing the instance class or the number of nodes will affect the upper limit of the storage space.

Autoscaling of a Single Instance

Log in to the GeminiDB console.
In the service list, choose Databases > GeminiDB Redis API.
On the Instances page, click the instance. The Basic Information page is displayed.
In the Total Storage Space area, click Auto Scale.

Figure 1 Auto Scale

Toggle on Auto Scale and specify the trigger condition and increment.

Figure 2 Configuring autoscaling parameters

**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 a specified threshold or the available storage 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. At least 1 GB is added each time.

Click OK.

Autoscaling Storage Space of Instances in Batches

Log in to the GeminiDB console.
In the service list, choose Databases > GeminiDB Redis API.
On the DB instance list page, select the instances you want to enable autoscaling for and click Auto Scale.

Figure 3 Autoscaling

Toggle on Autoscaling and specify the trigger condition and increment.

Figure 4 Configuring autoscaling parameters

**Table 2** Parameter description
Parameter	Description
Autoscaling	If you toggle on this switch, autoscaling is enabled.
Storage Usage	When the storage usage is greater than or equal to the threshold you set, the system automatically scales up your instance storage.
Increase By	Percentage of the current storage to be automatically scaled. The value can be 10, 15, or 20. At least 1 GB is added each time.