：UpdateServerGroupAttribute

The operation that you want to perform. Set the value to UpdateServerGroupAttribute.

The ID of the server group.

The new name of the server group.

The name must be 2 to 128 characters in length and can contain letters, digits, periods (.), underscores (_), and hyphens (-). The name must start with a letter.

Specifies whether to enable connection draining. Valid values:

• true: enables connection draining.
• false: disables connection draining.

The timeout period of connection draining. Unit: seconds. Valid values: 10 to 900.

The scheduling algorithm. Valid values:

• Wrr: Backend servers with higher weights receive more requests than backend servers with lower weights.
• rr: Requests are forwarded to backend servers in sequence.
• sch: Requests from the same source IP address are forwarded to the same backend server.
• tch: Four-element hashing is used. This value specifies consistent hashing that is based on four factors: source IP address, destination IP address, source port, and destination port. Requests that contain the same information based on the four factors are forwarded to the same backend server.
• qch: Requests that contain the same QUIC ID are forwarded to the same backend server.

Specifies whether to enable client IP preservation. Valid values:

• true: enables client IP preservation.
• false: disables client IP preservation.

Specifies whether to enable the health check feature. Valid values:

• true: enables the health check feature.
• false: disables the health check feature.

The protocol that is used for health checks. Valid values: TCP and HTTP.

The backend port that is used for health checks. Valid values: 0 to 65535. If you set the value to 0, the ports of backend servers are used for health checks.

The number of times that an unhealthy backend server must consecutively pass health checks before it is declared healthy. In this case, the health status is changed from fail to success. Valid values: 2 to 10.

The number of times that a healthy backend server must consecutively fail health checks before it is declared unhealthy. In this case, the health status is changed from success to fail. Valid values: 2 to 10.

The maximum timeout period of a health check response. Unit: seconds. Valid values: 1 to 300.

The interval between two consecutive health checks. Unit: seconds.

Valid values: 5 to 50.

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 (.).

The path to which health check requests are sent.

The path must be 1 to 80 characters in length, and can contain only letters, digits, and the following special characters: - / . % ? # & =. The path can also contain the following extended characters: _ ; ~ ! ( ) * [ ] @ $ ^ : ' , +. The path must start with a forward slash (/).

The HTTP status codes to return for health checks. Separate multiple HTTP status codes with commas (,).

Valid values: http_2xx (default), http_3xx, http_4xx, and http_5xx.

The HTTP method that is used for health checks. Valid values: GET and HEAD.

The ID of the region where the NLB instance is deployed.

You can call the DescribeRegions operation to query the available regions.

Specifies whether to only precheck the request. Valid values:

• true: checks the request without performing the UpdateServerGroupAttribute operation. The system checks the required parameters, request syntax, and limits. If the request fails the check, an error message is returned. If the request passes the check, the DryRunOperation error code is returned.
• false (default): sends the request. If the request passes the check, a 2xx HTTP status code is returned and the UpdateServerGroupAttribute operation is performed.

The client token that is used to ensure the idempotence of the request.

You can use the client to generate the value, but you must ensure that it is unique among different requests. The token can contain only ASCII characters.

The ID of the request.

The ID of the server group.

The ID of the asynchronous task.