UpdateServerGroupAttribute - Server Load Balancer - Alibaba Cloud Documentation Center

Updates the configuration of a Network Load Balancer (NLB) server group.

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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

nlb:UpdateServerGroupAttribute

update

*ServerGroup

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

None

Request parameters

Parameter	Type	Required	Description	Example
ServerGroupId	string	Yes	The ID of the server group.	sgp-atstuj3rtoptyui****
ServerGroupName	string	No	The new name of the server group. The name must be 2 to 128 characters in length, start with a letter or a Chinese character, and can contain digits, periods (.), underscores (_), and hyphens (-).	NLB_ServerGroup1
ConnectionDrainEnabled	boolean	No	Specifies whether to enable connection draining. Valid values: true false	false
ConnectionDrainTimeout	integer	No	The timeout period of connection draining. Unit: seconds. Valid values: 0 to 900.	10
Scheduler	string	No	The scheduling algorithm. Valid values: Wrr: weighted round-robin. Backend servers with higher weights receive more requests than backend servers with lower weights. Wlc: weighted least connections. Requests are distributed to backend servers based on their weights and the number of connections. If two backend servers have the same weight, the backend server that has fewer connections receives more requests. rr: round-robin. Requests are distributed to backend servers in sequence. sch: source IP hash. Requests from the same source IP address are distributed to the same backend server. tch: four-tuple hash. Requests are distributed to backend servers based on a hash of the four-tuple, which consists of the source IP address, destination IP address, source port, and destination port. This ensures that requests from the same flow are distributed to the same backend server. qch: QUIC ID hash. Requests with the same QUIC ID are distributed to the same backend server. Note You can set the scheduling algorithm to qch only when the backend protocol is UDP.	Wrr
PreserveClientIpEnabled	boolean	No	Specifies whether to enable client IP address preservation. Valid values: true false Note If PreserveClientIpEnabled is set to false and the server group is associated with a TCPSSL listener, you cannot change the value of this parameter to true.	false
HealthCheckConfig	object	No	The health check configurations.
HealthCheckEnabled	boolean	No	Specifies whether to enable the health check feature. Valid values: true false	false
HealthCheckType	string	No	The health check protocol. Valid values: TCP HTTP UDP	TCP
HealthCheckConnectPort	integer	No	The port that is used for health checks on backend servers. Valid values: 0 to 65535. If you set the value to 0, the port of a backend server is used for health checks.	0
HealthyThreshold	integer	No	The number of consecutive health checks that a backend server must pass before it is declared healthy. In this case, the health check status is changed from failed to success. Valid values: 2 to 10.	3
UnhealthyThreshold	integer	No	The number of consecutive health checks that a backend server must fail before it is declared unhealthy. In this case, the health check status is changed from success to failed. Valid values: 2 to 10.	3
HealthCheckConnectTimeout	integer	No	The maximum timeout period of a health check response. Unit: seconds. Valid values: 1 to 300. Default value: 5.	100
HealthCheckInterval	integer	No	The interval at which health checks are performed. Unit: seconds. Default value: 5. If HealthCheckType is set to TCP or HTTP, the value must be in the range of 1 to 50. If HealthCheckType is set to UDP, the value must be in the range of 1 to 300. Make sure that the interval is greater than or equal to the response timeout period. This prevents UDP probes from being marked as unresponsive due to timeouts.	5
HealthCheckDomain	string	No	The domain name that is used for health checks. Valid values: $SERVER_IP: the private IP address of a backend server. domain: a specific domain name. The domain name must be 1 to 80 characters in length and can contain lowercase letters, digits, hyphens (-), and periods (.). Note This parameter takes effect only when HealthCheckType is set to HTTP.	$SERVER_IP
HealthCheckUrl	string	No	The path that is used for health checks. The path must be 1 to 80 characters in length. It can contain letters, digits, and the following special characters: `-/.%?#&=`. It can also contain the following extended characters: `_;~!()[]@$^:',+`. The path must start with a forward slash (/). Note* This parameter takes effect only when HealthCheckType is set to HTTP.	/test/index.html
HealthCheckHttpCode	array	No	The HTTP status codes that indicate a healthy backend server. You can specify multiple HTTP status codes. Separate them with commas (,). Valid values: http_2xx (default), http_3xx, http_4xx, and http_5xx. Note This parameter takes effect only when HealthCheckType is set to HTTP.
	string	No	The HTTP status codes that indicate a healthy backend server. You can specify multiple HTTP status codes. Separate them with commas (,). Valid values: http_2xx (default), http_3xx, http_4xx, and http_5xx. Note This parameter takes effect only when HealthCheckType is set to HTTP.	http_2xx
HttpCheckMethod	string	No	The HTTP method that is used for health checks. Valid values: GET and HEAD. Note This parameter takes effect only when HealthCheckType is set to HTTP.	GET
HealthCheckReq	string	No	The request string for UDP health checks. The string can contain only letters and digits and must be at most 512 characters in length.	hello
HealthCheckExp	string	No	The response string for UDP health checks. The string can contain only letters and digits and must be at most 512 characters in length.	ok
HealthCheckHttpVersion	string	No	The version of the HTTP protocol that is used for health checks. Valid values: HTTP1.0 and HTTP1.1. Note This parameter takes effect only when HealthCheckType is set to HTTP.	HTTP1.0
RegionId	string	No	The ID of the region where the NLB instance is deployed. 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. Valid values: true: performs a dry run but does not update the server group. The system checks the required parameters, the request format, and business 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): sends a normal request. If the request passes the check, an HTTP 2xx status code is returned and the operation is performed.	false
ClientToken	string	No	The client token that is used to ensure the idempotence of the request. You can use the client to generate a token, but you must make sure that the token is unique among different requests. The token can contain only ASCII characters. Note If you do not specify this parameter, the system automatically uses the RequestId of the API request as the ClientToken. The RequestId may be different for each API request.	123e4567-e89b-12d3-a456-426655440000

Response elements

Element	Type	Description	Example
	object	The configurations of the server group.
RequestId	string	The request ID.	54B48E3D-DF70-471B-AA93-08E683A1B45
ServerGroupId	string	The ID of the server group.	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	IllegalParam.%s	The param of %s is illegal.
400	SystemBusy	System is busy, please try again later.
400	IllegalParam.healthCheckDomain	The parameter of healthCheckConfig.healthCheckDomain is illegal.	The healthCheckDomain in the health check configuration is invalid. Check the input parameters.
400	IlleagalParam.healthCheckUrl	The parameter of healthCheckUrl in healthCheckConfig is illegal.	The URL of the health check used in the health check setting is invalid.
400	OperationDenied.UidNotAllowQuic29	The operation is not allowed because of uid not allow quic29 version.
400	IllegalParam	The param of %s is illegal.
400	DryRunOperation	Request validation has been passed with DryRun flag set.	Request validation has been passed with DryRun flag set.
400	IllegalParam.ServerGroupName	The param of ServerGroupName is illegal.
400	IllegalParam.PreserveClientIpSwitch	The server group associated with the tcpssl listener does not support enabling PreserveClientIp.	The server group associated with the tcpssl listener does not support enabling PreserveClientIp.
403	Forbidden.NoPermission	Authentication is failed for NoPermission.	Authentication is failed for NoPermission.
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.