Creating an AS Group

Function

An AS group is a collection of instances that are used in 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 balance settings.

Each account can create a maximum of 10 AS groups by default.
If a load balancer is associated with an AS group, AS automatically associates the load balancer with or dissociates the load balancer from instances when the instances are added to or removed from the AS group.
If ELB health check is enabled for an AS group, the instances in the AS group must use all the listening ports of each load balancer for health check. You can configure these ports in the security group of the instances. For details, see Adding a Security Group Rule.
- If you add multiple load balancers to an AS group, an instance is considered healthy only when all load balancers declare that it is healthy. If any load balancer detects that the instance is unhealthy, the instance will be removed from the AS group.
- If you add a load balancer that has multiple listening ports to an AS group, an instance is considered healthy only when all the ports detect the instance is healthy. If the instance is detected unhealthy by any of the ports, the instance will be removed from the AS group.
If you add a load balancer that has multiple listening ports to an AS group, you are advised to create AS policies based on ECS metrics, rather than network metrics or application metrics. If a network metric or an application metric is used, scale-out and scale-in actions may happen at the same time.
If you add a load balancer that has multiple listening ports to an AS group, AS can complete a scale-out or scale-in action only when the load balancer listens or no longer listens on all these ports on the instances to be added or removed. Otherwise, AS will release the instances to be added and create new ones in the scale-out action or will not release the instances to be removed in the scale-in action.

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

**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 1. The value is an integer ranging from 0 to 300.
cool_down_time	No	Integer	Specifies the cooldown period (in seconds). The value ranges from 0 to 86400 and defaults to 300. After a scaling action is complete, the cooldown period starts. During the cooldown period, AS denies all scaling requests triggered by alarm-based policies. Scaling requests triggered manually or by scheduled or periodic policies are not affected. NOTE: When an AS group scales out, scale-in requests triggered manually or by scheduled and periodic policies will be executed immediately after the scale-out is complete, without being affected by the cooldown period. When an AS group scales in, scale-out requests triggered manually or by scheduled and periodic policies will be executed immediately after the scale-in is complete, without being affected by the cooldown period.
lb_listener_id	No	String	Specifies the ID of a listener added to a load balancer. You can add up to six listeners. Separate listener IDs with commas (,). For how to obtain a listener ID, see Querying Load Balancers. This parameter is alternative to lbaas_listeners.
lbaas_listeners	No	Array of lbaas_listeners objects	Specifies information about a load balancer. You can add up to six load balancers. This parameter is in list data structure. For details, see Table 3. For how to obtain information about a load balancer, see Querying Backend Server Groups. This parameter is alternative to lb_listener_id.
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. For details, see Regions and Endpoints.
networks	Yes	Array of networks objects	Specifies network information. You can select up to five subnets. The first subnet you select is used by the primary NICs of ECSs by default. For how to obtain information about subnets, see Querying Subnets. For the information about the data structure, see Table 4.
security_groups	No	Array of security_groups objects	Specifies the security group information. Only one security group can be selected. For how to obtain security group information, see Querying Security Groups. For the information about the data structure, see Table 7. If a security group is specified both in the AS configuration and the AS group, scaled-out instances will be added to the security group specified in the AS configuration. If a security group is not specified in either of them, scaled-out instances will be added to the default security group. For your convenience, specify a 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 that comes with AS.
health_periodic_audit_time	No	Integer	Specifies the health check interval. 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 health 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 parameter has been discarded. You can configure notifications for the AS group by referring to Notifications.
delete_publicip	No	Boolean	Specifies whether to delete the EIPs bound to ECS instances when the instances are removed from the AS group during scale-in actions. The value can be true or false. The default value is false. true: The EIPs bound to ECSs will be released when the ECSs are removed. If the EIPs are billed on a yearly/monthly basis, they will not be released when the ECSs are removed. false: The EIPs bound to ECSs will be unbound but will not be released when the ECSs are removed.
delete_volume	No	Boolean	Specifies whether to delete the data disks attached to ECS instances when the instances are removed from the AS group during scale-in actions. The value can be true or false. The default value is false. true: The data disks attached to ECSs will be released when the ECSs are removed. If the data disks are billed a yearly/monthly basis, they will not be deleted when ECSs are removed. false: The data disks attached to ECSs will be detached but will not be released when the ECSs are removed.
enterprise_project_id	No	String	Specifies the enterprise project ID, which is used to specify the enterprise project to which the AS group belongs. If the value is 0 or left blank, the AS group belongs to the default enterprise project. If the value is a UUID, the AS group belongs to the enterprise project corresponding to the UUID.. For how to obtain an enterprise project ID, see Querying Enterprise Projects. If an enterprise project is configured for an AS group, ECSs created in this AS group also belong to this enterprise project. Otherwise, the default enterprise project will be used. NOTE: For details about enterprise project features, see Enterprise Project Management Service.
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 AS scales out the AS group, it preferentially distributes instances evenly across AZs in the available_zones list. If it fails in the target AZ, it selects another AZ based on the PICK_FIRST policy. PICK_FIRST: When AS scales out the AS group, the target AZ is 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.
iam_agency_name	No	String	Specifies the agency name, in 1 to 64 characters. iam_agency_name is not transferred if it is set to null. iam_agency_name is transferred if it is left blank or has a value.
tags	No	Array of tags objects	Creates tags and adds them the AS group. Each AS group can have a maximum of 10 tags. For details, see Table 8.

**Table 3** **lbaas_listeners** field description
Parameter	Mandatory	Type	Description
pool_id	Yes	String	Specifies the backend server group ID.
protocol_port	Yes	Integer	Specifies the port configured for the backend server group, which is the port on which a backend server listens for traffic. The port ranges from 1 to 65535.
weight	Yes	Integer	Specifies the weight, which determines the percentage of requests a backend server processes. The value of this parameter ranges from 0 to 100.
protocol_version	No	String	Specifies the version of instance IP addresses to be associated with the load balancer. The value can be ipv4 or ipv6. NOTE: Instances in an AS group do not support IPv4/IPv6 dual-stack on multiple NICs. IPv4/IPv6 dual-stack is only available for the first NIC that supports both IPv4 and IPv6. The NIC may be a primary NIC or an extension NIC. Only ECSs with flavors that support IPv6 can use IPv4/IPv6 dual-stack networks. If you want to select IPv6 for this parameter, make sure that you have selected such ECS flavors in a supported region. If you add two or more load balancers whose pool_id, protocol_port, and protocol_version settings are totally same, deduplication will be performed.

**Table 4** **networks** field description
Parameter	Mandatory	Type	Description
id	Yes	String	Specifies the subnet ID.
ipv6_enable	No	Boolean	Specifies whether to support IPv6 addresses. true: indicates that the NIC supports IPv6 addresses. false: indicates that the NIC does not support IPv6 addresses. The default value is false.
ipv6_bandwidth	No	ipv6_bandwidth object	Specifies the shared bandwidth of an IPv6 address. This parameter is left blank by default, indicating that no shared IPv6 bandwidth is bound.
allowed_address_pairs	No	Array of allowed_address_pairs objects	Specifies whether to allow the system to check the source and destination addresses.

**Table 5** **ipv6_bandwidth** field description
Parameter	Mandatory	Type	Description
id	Yes	String	Specifies the ID of the shared bandwidth of an IPv6 address.

**Table 6** **allowed_address_pairs** field description
Parameter	Mandatory	Type	Description
ip_address	No	String	Specifies whether to allow the system to check the source and destination addresses. This function is enabled by default. This parameter cannot be left empty. To disable this function, set the value to 1.1.1.1/0. To enable this function, set a value other than 1.1.1.1/0.

**Table 7** **security_groups** field description
Parameter	Mandatory	Type	Description
id	Yes	String	Specifies the security group ID.

**Table 8** **tags** field description
Parameter	Mandatory	Type	Description
key	Yes	String	Specifies the tag key. A key can contain up to 36 Unicode characters. It cannot be left blank. The tag key of a resource must be unique. The key of the tag can contain only uppercase letters, lowercase letters, digits, underscores (_), and hyphens (-).
value	No	String	Specifies the key value. A value can contain up to 43 Unicode characters and can be an empty string. The value can contain only uppercase letters, lowercase letters, digits, underscores (_), hyphens (-), and periods (.).

Example Request

This example creates an AS group with the name GroupNameTest, the AS configuration ID 47683a91-93ee-462a-a7d7-484c006f4440, the VPC ID a8327883-6b07-4497-9c61-68d03ee193a, the NIC ID 3cd35bca-5a10-416f-8994-f79169559870, the maximum number of instances of 10, the expected number of instances of 0, the minimum number of instances of 0, and the health check method of ECS health check, and the multi-AZ scaling policy of PICK_FIRST. The enterprise project is specified by you.

{
    "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"
        }
    ],
    "enterprise_project_id":"c92b1a5d-6f20-43f2-b1b7-7ce35e58e413",
    "multi_az_priority_policy":"PICK_FIRST",
    "iam_agency_name":"test",
    "tags":[{"key":"1"}]
}

Response

**Table 9** Response parameters
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 to process the request.
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.