UpdateServerGroupServersAttribute - Server Load Balancer

Updates the configurations of backend servers in a server group, such as their weight and description.

Operation description

UpdateServerGroupServersAttribute is an asynchronous operation. After you send a request, the system returns a request ID and runs the task in the background. The configurations of the backend servers are not updated in real time.

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

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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

alb:UpdateServerGroupServersAttribute

update

*ServerGroup

acs:alb:{#regionId}:{#accountId}:servergroup/{#servergroupId}

*Instance

acs:ecs:{#regionId}:{#accountId}:ecs/{#ecsId}

None

Request parameters

Parameter	Type	Required	Description	Example
ServerGroupId	string	Yes	The ID of the server group.	sgp-atstuj3rtop****
Servers	array<object>	Yes	The backend servers. You can specify up to 40 servers in each call.
	object	No	The backend server.
Description	string	No	The description of the backend server. The description must be 2 to 256 characters in length and cannot start with http:// or https://.	test
Port	integer	No	The port used by the backend server. Valid values: 1 to 65535. Note This parameter is not required if ServerType is set to Fc.	80
ServerId	string	No	The ID of the backend server. If you set ServerType to Ecs, Eni, or Eci, set this parameter to the ID of the ECS instance, elastic network interface (ENI), or elastic container instance (ECI). If you set ServerType to Ip, set this parameter to an IP address. If you set ServerType to Fc, set this parameter to the Alibaba Cloud Resource Name (ARN) of the Function Compute function.	i-bp1f9kdprbgy9uiu****
ServerIp	string	No	The IP address.	192.168.1.1
ServerType	string	Yes	The type of the backend server. Valid values: Ecs: an ECS instance. Eni: an ENI. Eci: an ECI. Ip: an IP address. Fc: a Function Compute function.	Ecs
Weight	integer	No	The weight of the backend server. Valid values: 0 to 100. Default value: 100. If you set the weight to 0, no requests are forwarded to the backend server. Note This parameter is not required if ServerType is set to Fc.	100
ClientToken	string	No	The client token that is used to ensure the idempotence of the request. Generate a token that is unique among different requests. The token can contain only ASCII characters. Note If you do not specify this parameter, the system uses the RequestId of the request as the ClientToken. The RequestId of each request is unique.	593B0448-D13E-4C56-AC0D-FDF0******
DryRun	boolean	No	Specifies whether to perform a dry run. Valid values: true: performs a dry run. The system checks the required parameters, request format, and service limits, but does not update the configurations, such as the weight and description, of the backend servers. 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): sends a normal request. After the request passes the check, the system returns an HTTP 2xx status code and completes the operation.	false

Response elements

Element	Type	Description	Example
	object	The returned data.
JobId	string	The ID of the asynchronous task.	72dcd26b-f12d-4c27-b3af-18f6aed5****
RequestId	string	The request ID.	365F4154-92F6-4AE4-92F8-7FF3*****

Examples

Success response

JSON format

{
  "JobId": "72dcd26b-f12d-4c27-b3af-18f6aed5****",
  "RequestId": "365F4154-92F6-4AE4-92F8-7FF3*****"
}

Error codes

HTTP status code	Error code	Error message	Description
400	IncorrectStatus.ServerGroup	The status of %s [%s] is incorrect.	The status of %s [%s] is incorrect.
400	ResourceInConfiguring	The specified resource of %s is being configured. Please try again later.
403	Forbidden.ServerGroup	Authentication has failed for ServerGroup.
404	ResourceNotFound.ServerGroup	The specified resource %s is not found.
404	ResourceNotFound.BackendServer	The specified resource %s is not found.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.