Use UpdateServerGroupServersAttribute to modify the weight and description of backend servers in a server group - Server Load Balancer - Alibaba Cloud - Server Load Balancer

Modifies the weights and descriptions of backend servers in a server group of a Network Load Balancer (NLB) instance.

Operation description

UpdateServerGroupServersAttribute is an asynchronous operation. After a request is sent, the system returns a request ID and runs the task in the background.

You can call the ListServerGroups operation to query the status of a server group.
- If a server group is in the Configuring state, the server group is being modified.
- If a server group is in the Available state, the server group is running.
You can call the ListServerGroupServers operation to query the status of a backend server.
- If a backend server is in the Configuring state, it indicates that the backend server is being modified.
- If a backend server is in the Available state, it indicates that the backend server is running.

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Test

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

nlb:UpdateServerGroupServersAttribute

update

*ServerGroup

acs:nlb:{#regionId}:{#accountId}:servergroup/{#ServerGroupId}

None

Request parameters

Parameter	Type	Required	Description	Example
ServerGroupId	string	Yes	The server group ID.	sgp-atstuj3rtoptyui****
Servers	array<object>	Yes	The backend servers. You can specify at most 200 backend servers in each call.
	object	No	The backend servers. You can specify at most 200 backend servers in each call.
ServerId	string	Yes	The backend server ID. If the server group is of the Instance type, set this parameter to the IDs of servers of the Ecs, Eni, or Eci type. If the server group is of the Ip type, set this parameter to IP addresses.	ecs-bp67acfmxazb4p****
ServerType	string	Yes	The type of the backend server. Valid values: Ecs: Elastic Compute Service (ECS) instance Eni: elastic network interface (ENI) Eci: elastic container instance Ip: IP address	Ecs
ServerIp	string	No	The IP addresses of servers. If the server group type is Ip, set the ServerId parameter to IP addresses.	192.168.6.6
Port	integer	Yes	The port used by the backend server. Valid values: 1 to 65535. Note This parameter cannot be modified.	443
Weight	integer	No	The weight of the backend server. Valid values: 0 to 100. Default value: 100. If set to 0, no requests are forwarded to the server.	100
Description	string	No	The description of the backend server. The description must be 2 to 256 characters in length, and can contain letters, digits, commas (,), periods (.), semicolons (;), forward slashes (/), at signs (@), underscores (_), and hyphens (-).	test
RegionId	string	No	The region ID of the NLB instance. You can call the DescribeRegions operation to query the most recent region list.	cn-hangzhou
DryRun	boolean	No	Specifies whether to perform a dry run, without sending the actual request. Valid values: true: performs only a dry run. The system checks the request for potential issues, including missing parameter values, incorrect request syntax, and service limits. If the request fails the dry run, an error message is returned. If the request passes the dry run, the `DryRunOperation` error code is returned. false (default): performs a dry run and sends the actual request. If the request passes the dry run, a 2xx HTTP status code is returned and the operation is performed.	false
ClientToken	string	No	The client token used to ensure the idempotence of the request. You can use the client to generate this value. Ensure that the value is unique among all requests. Only ASCII characters are allowed. Note If you do not specify this parameter, the system uses the RequestId value. Each request has a unique RequestId.	123e4567-e89b-12d3-a456-426655440000

Response elements

Element	Type	Description	Example
	object	Updates the configurations of backend servers in a server group.
RequestId	string	The request ID.	54B48E3D-DF70-471B-AA93-08E683A1B45
ServerGroupId	string	The server group ID.	sgp-atstuj3rtoptyui****
JobId	string	The ID of the asynchronous task.	72dcd26b-f12d-4c27-b3af-18f6aed5****

Examples

Success response

JSON format

{
  "RequestId": "54B48E3D-DF70-471B-AA93-08E683A1B45",
  "ServerGroupId": "sgp-atstuj3rtoptyui****",
  "JobId": "72dcd26b-f12d-4c27-b3af-18f6aed5****"
}

Error codes

HTTP status code	Error code	Error message	Description
400	IncorrectStatus.serverGroup	The status of servergroup [%s] is incorrect.	The current operation cannot be performed on the server group as its status is unavailable. Please check if the server group is currently undergoing any other operations.
400	Conflict.Lock	The Lock [%s] is conflict.	The specific resource is conflict.
400	IllegalParam.%s	The param of %s is illegal.
400	MissingParam.%s	The parameter of %s is missing.
403	Forbidden.%s	Authentication is failed for %s.
403	Forbidden.NoPermission	Authentication is failed for NoPermission.	Authentication is failed for NoPermission.
404	ResourceNotFound.BackendServer	The specified resource of BackendServer is not found.	The specified backend server resource was not found. Please check the input parameters.
404	ResourceNotFound.serverGroup	The specified resource of serverGroup is not found.	The specified resource of serverGroup is not found. Please check the input parameters.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.