Use SetBackendServers to specify weights for backend servers - Server Load Balancer - Alibaba Cloud - Server Load Balancer

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RAM authorization

The table below describes the authorization required to call this API. You can define it in a Resource Access Management (RAM) policy. The table's columns are detailed below:

Action: The actions can be used in the Action element of RAM permission policy statements to grant permissions to perform the operation.
API: The API that you can call to perform the action.
Access level: The predefined level of access granted for each API. Valid values: create, list, get, update, and delete.
Resource type: The type of the resource that supports authorization to perform the action. It indicates if the action supports resource-level permission. The specified resource must be compatible with the action. Otherwise, the policy will be ineffective.
- For APIs with resource-level permissions, required resource types are marked with an asterisk (*). Specify the corresponding Alibaba Cloud Resource Name (ARN) in the Resource element of the policy.
- For APIs without resource-level permissions, it is shown as All Resources. Use an asterisk (*) in the Resource element of the policy.
Condition key: The condition keys defined by the service. The key allows for granular control, applying to either actions alone or actions associated with specific resources. In addition to service-specific condition keys, Alibaba Cloud provides a set of common condition keys applicable across all RAM-supported services.
Dependent action: The dependent actions required to run the action. To complete the action, the RAM user or the RAM role must have the permissions to perform all dependent actions.

Action

Access level

Resource type

Condition key

Dependent action

slb:SetBackendServers

update

instance

acs:ecs:{#regionId}:{#accountId}:instance/{#instanceId}

*loadbalancer

acs:slb:{#regionId}:{#accountId}:loadbalancer/{#loadbalancerId}

ecs:tag
slb:tag
slb:tag

None

Request parameters

Parameter	Type	Required	Description	Example
RegionId	string	No	The region ID of the Classic Load Balancer (CLB) instance.	cn-hangzhou
LoadBalancerId	string	Yes	The ID of the Classic Load Balancer (CLB) instance.	lb-bp1qjwo61pqz3a******
BackendServers	string	No	The list of backend servers to add. The list contains the following parameters: ServerId: String, required. The instance ID of the backend server. The value can be the ID of an ECS instance, an ENI instance, or an ECI instance. If ServerId is set to the ID of an ENI or ECI instance, the Type parameter is required. Weight: The weight of the backend server. Valid values: 0 to 100. Default value: 100. If the value is set to 0, no requests are forwarded to the backend server. Description: String, optional. The description of the backend server. The description must be 1 to 80 characters in length and can contain Chinese characters, letters, digits, hyphens (-), forward slashes (/), periods (.), and underscores (_). Type: The server type of the backend server. Valid values: ecs: ECS instance (default). eni: network interface controller (NIC) instance. eci: Elastic Container Instance (ECI) instance. Note Only guaranteed-performance instances support adding eni and eci types of backend servers. ServerIp: The IP address of the ENI or ECI instance. Examples: Mount an ECS instance: `[{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Description":"test-112" }]` Mount an ENI: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Description":"test-112" }]` Mount an ENI with multiple IP addresses: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Description":"test-113" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166..", "Description":"test-113" }]` Mount an ECI instance: `[{ "ServerId": "eci-xxxxxxxxx", "Weight": "100", "Type": "eci", "ServerIp": "192.168..", "Description":"test-114" }]` Note Only backend servers in the running state can be added to a Server Load Balancer instance. You can add up to 20 backend servers in each call.	[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Description":"test-112" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166..", "Description":"test-113" }]

Response elements

Element	Type	Description	Example
	object
LoadBalancerId	string	The ID of the Classic Load Balancer (CLB) instance.	lb-bp1qjwo61pqz3a******
RequestId	string	The request ID.	365F4154-92F6-4AE4-92F8-7F******
BackendServers	object
BackendServer	array<object>	The list of backend servers.
	object	The list of backend servers.
Type	string	The type of backend server. Valid values: ecs (default): ECS instance eni: ENI eci: elastic container instance	eni
Weight	string	The weight of the backend server.	100
Description	string	The description of the backend server.	The description of the backend server.
ServerId	string	The ID of the server group.	eni-hhshhs****

Examples

Success response

JSON format

{
  "LoadBalancerId": "lb-bp1qjwo61pqz3a******",
  "RequestId": "365F4154-92F6-4AE4-92F8-7F******",
  "BackendServers": {
    "BackendServer": [
      {
        "Type": "eni",
        "Weight": "100",
        "Description": "The description of the backend server.",
        "ServerId": "eni-hhshhs****"
      }
    ]
  }
}

Error codes

HTTP status code	Error code	Error message	Description
400	Mismatched.ZoneId	The zone of the server is not matched with the cloud box loadbalancer.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.