Creating an AS Group

Function

An AS group consists of a collection of instances that apply to the same scenario. It is the basis for enabling or disabling AS policies and performing scaling actions. An AS group specifies parameters, such as the maximum number of instances, expected number of instances, minimum number of instances, VPC, subnet, and load balancing.

Each user can create a maximum of 10 AS groups by default.
If ELB is configured, AS automatically binds or unbinds a load balancer to or from an instance when the instance is added or removed from the AS group.
If an AS group uses ELB health check, the listening ports on the load balancers must be enabled for the instances in the AS group. Enable the listening ports in security groups.

URI

POST /autoscaling-api/v1/{project_id}/scaling_group

**Table 1** Parameter description
Parameter	Mandatory	Type	Description
project_id	Yes	String	Specifies the project ID.

Request Message

Request parameters

**Table 2** Request parameters
Parameter	Mandatory	Type	Description
scaling_group_name	Yes	String	Specifies the AS group name. The name contains only letters, digits, underscores (_), and hyphens (-), and cannot exceed 64 characters.
scaling_configuration_id	Yes	String	Specifies the AS configuration ID, which can be obtained using the API for querying AS configurations. For details, see Querying AS Configurations.
desire_instance_number	No	Integer	Specifies the expected number of instances. The default value is the minimum number of instances. The value ranges from the minimum number of instances to the maximum number of instances.
min_instance_number	No	Integer	Specifies the minimum number of instances. The default value is 0.
max_instance_number	No	Integer	Specifies the maximum number of instances. The default value is 0.
cool_down_time	No	Integer	Specifies the cooldown period (in seconds). The value ranges from 0 to 86400 and is 300 by default. After a scaling action is triggered, the system starts the cooldown period. During the cooldown period, scaling actions triggered by alarms will be denied. Scheduled, periodic, and manual scaling actions are not affected.
lbaas_listeners	No	Array of lbaas_listeners objects	Specifies information about an enhanced load balancer. The system supports the binding of up to six load balancers. This parameter is in list data structure. For details, see Table 3.
available_zones	No	Array of strings	Specifies the AZ information. The instances added in a scaling action will be created in a specified AZ. If you do not specify an AZ, the system automatically specifies one.
networks	Yes	Array of networks objects	Specifies network information. The system supports up to five subnets. The first subnet transferred serves as the primary NIC of the ECS by default. This parameter is in data structure. For details, see Table 4.
security_groups	No	Array of security_groups objects	Specifies the security group information. A maximum of one security group can be selected. This parameter is in data structure. For details, see Table 5. If the security group is specified both in the AS configuration and AS group, scaled ECS instances will be added to the security group specified in the AS configuration. If the security group is not specified in either of them, scaled ECS instances will be added to the default security group. For your convenience, you are advised to specify the security group in the AS configuration.
vpc_id	Yes	String	Specifies the VPC ID, which can be obtained using the API for querying VPCs. For details, see "Querying VPCs" in Virtual Private Network API Reference.
health_periodic_audit_method	No	String	Specifies the health check method for instances in the AS group. The health check methods include ELB_AUDIT and NOVA_AUDIT. When load balancing is configured for an AS group, the default value is ELB_AUDIT. Otherwise, the default value is NOVA_AUDIT. ELB_AUDIT: indicates the ELB health check, which takes effect in an AS group with a listener. NOVA_AUDIT: indicates the ECS instance health check, which is the health check method delivered with AS.
health_periodic_audit_time	No	Integer	Specifies the instance health check period. The value can be 1, 5, 15, 60, or 180 in the unit of minutes. If this parameter is not specified, the default value is 5. If the value is set to 0, health check is performed every 10 seconds.
health_periodic_audit_grace_period	No	Integer	Specifies the grace period for instance health check. The unit is second and the value ranges from 0 to 86400. The default value is 600. The health check grace period starts after an instance is added to an AS group and is enabled. The AS group will start checking the instance status only after the grace period ends. This parameter is valid only when the instance health check method of the AS group is ELB_AUDIT.
instance_terminate_policy	No	String	Specifies the instance removal policy. OLD_CONFIG_OLD_INSTANCE (default): The earlier-created instances based on the earlier-created AS configurations are removed first. OLD_CONFIG_NEW_INSTANCE: The later-created instances based on the earlier-created AS configurations are removed first. OLD_INSTANCE: The earlier-created instances are removed first. NEW_INSTANCE: The later-created instances are removed first.
notifications	No	Array of strings	Specifies the notification mode. EMAIL refers to notification by email. This notification mode has been canceled. You are advised to configure the notification function for the AS group. For details, see Notifications.
delete_publicip	No	Boolean	Specifies whether to delete the EIP bound to the ECS when deleting the ECS. The value can be true or false. The default value is false. true: deletes the EIP bound to the ECS when deleting the ECS. false: only unbinds the EIP bound to the ECS when deleting the ECS.
delete_volume	No	Boolean	Specifies whether to delete the data disks attached to the ECS when deleting the ECS. The value can be true or false. The default value is false. true: deletes the data disks attached to the ECS when deleting the ECS. false: only detaches the data disks attached to the ECS when deleting the ECS.
multi_az_priority_policy	No	String	Specifies the priority policy used to select target AZs when adjusting the number of instances in an AS group. EQUILIBRIUM_DISTRIBUTE (default): When adjusting the number of instances, ensure that instances in each AZ in the available_zones list is evenly distributed. If instances cannot be added in the target AZ, select another AZ based on the PICK_FIRST policy. PICK_FIRST: When adjusting the number of instances, target AZs are determined in the order in the available_zones list.
description	No	String	Specifies the description of the AS group. The value can contain 1 to 256 characters.

**Table 3** **lbaas_listeners** field description
Parameter	Mandatory	Type	Description
pool_id	Yes	String	Specifies the backend ECS group ID.
protocol_port	Yes	Integer	Specifies the backend protocol ID, which is the port on which a backend ECS listens for traffic. The port ID ranges from 1 to 65535.
weight	Yes	Integer	Specifies the weight, which determines the portion of requests a backend ECS processes when being compared to other backend ECSs added to the same listener. The value of this parameter ranges from 0 to 100.

**Table 4** **networks** field description
Parameter	Mandatory	Type	Description
id	Yes	String	Specifies the subnet ID.

**Table 5** **security_groups** field description
Parameter	Mandatory	Type	Description
id	Yes	String	Specifies the security group ID.

Example request
The following example shows how to create an AS group:
- The AS group is named GroupNameTest.
- The AS configuration ID is 47683a91-93ee-462a-a7d7-484c006f4440.
- The VPC ID is a8327883-6b07-4497-9c61-68d03ee193a, and the network ID is 3cd35bca-5a10-416f-8994-f79169559870.
- The maximum number of instances is 10, the expected number of instances is 0, and the minimum number of instances is 0.
- The health check method is ECS health check.
- When adjusting the number of instances, select target AZ based on the PICK FIRST policy.
The request example is as follows:
```
{
    "scaling_group_name": "GroupNameTest",
    "scaling_configuration_id": "47683a91-93ee-462a-a7d7-484c006f4440",
    "desire_instance_number": 0,
    "min_instance_number": 0,
    "max_instance_number": 10,
    "health_periodic_audit_method": "NOVA_AUDIT",
    "vpc_id": "a8327883-6b07-4497-9c61-68d03ee193a",
    "available_zones": ["XXXa","XXXb"],
    "networks": [
        {
            "id": "3cd35bca-5a10-416f-8994-f79169559870"
        }
    ],
    "multi_az_priority_policy": "PICK_FIRST",
    
}
```

Response Message

Response parameters

**Table 6** Response parameter
Parameter	Type	Description
scaling_group_id	String	Specifies the AS group ID.

Example response

{
    "scaling_group_id": "a8327883-6b07-4497-9c61-68d03ee193a1"
}

Returned Values

Normal
200

Abnormal

Returned Value	Description
400 Bad Request	The server failed to process the request.
401 Unauthorized	You must enter the username and password to access the requested page.
403 Forbidden	You are forbidden to access the requested page.
404 Not Found	The server could not find the requested page.
405 Method Not Allowed	You are not allowed to use the method specified in the request.
406 Not Acceptable	The response generated by the server could not be accepted by the client.
407 Proxy Authentication Required	You must use the proxy server for authentication so that the request can be processed.
408 Request Timeout	The request timed out.
409 Conflict	The request could not be processed due to a conflict.
500 Internal Server Error	Failed to complete the request because of an internal service error.
501 Not Implemented	Failed to complete the request because the server does not support the requested function.
502 Bad Gateway	Failed to complete the request because the request is invalid.
503 Service Unavailable	Failed to complete the request because the system is unavailable.
504 Gateway Timeout	A gateway timeout error occurred.