ModifyVServerGroupBackendServers - Classic Load Balancer| Alibaba Cloud Documentation Center

You can call this operation to replace the backend servers in a specified vServer group. To modify the configurations of the backend servers, such as their weights, you can call the SetVServerGroupAttribute operation.

Debugging

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer. OpenAPI Explorer dynamically generates the sample code of the operation for different SDKs.

Request parameters


Parameter	Type	Required	Example	Description
Action	String	Yes	ModifyVServerGroupBackendServers	The operation that you want to perform. Set the value to ModifyVServerGroupBackendServers.
RegionId	String	Yes	cn-hangzhou	The ID of the region where the Classic Load Balancer (CLB) instance is deployed.
VServerGroupId	String	Yes	rsp-cige6j****	The ID of the vServer group.
OldBackendServers	String	No	[{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }]	The list of backend servers that you want to replace in the vServer group. You can specify at most 20 backend servers for a vServer group in each call. ServerId: required. The ID of the Elastic Compute Service (ECS) instance or elastic network interface (ENI) that serves as a backend server. This parameter must be of the STRING type. Port: required. The port that is used by the backend server. This parameter must be of the INTEGER type. Valid values: 1 to 65535. Weight: required. The weight of the backend server. This parameter must be of the INTEGER type. Valid values: 0 to 100. Description: optional. The description of the backend server. This parameter must be of the STRING type. The description must be 1 to 80 characters in length, and can contain letters, digits, hyphens (-), forward slashes (/), periods (.),and underscores (_). Type: the type of backend server. This parameter must be of the STRING type. Valid values: ecs: an ECS instance. This is the default value. eni: an ENI. ServerIp: the IP address of the ECS instance or ENI. Examples: An ECS instance: `[{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }]` An ENI: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Port":"80","Description":"test-112" }]` An ENI with multiple IP addresses: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Port":"80","Description":"test-112" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166..", "Port":"80","Description":"test-113" }]`
NewBackendServers	String	No	[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Port":"80","Description":"test-112" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166..", "Port":"80","Description":"test-113" }]	The list of new backend servers that you want to use to replace those in the vServer group. You can specify at most 20 backend servers for a vServer group in each call. ServerId: required. The ID of the ECS instance or ENI that serves as a backend server. This parameter must be of the STRING type. Port: required. The port that is used by the backend server. This parameter must be of the INTEGER type. Valid values: 1 to 65535. Weight: required. The weight of the backend server. This parameter must be of the INTEGER type. Valid values: 0 to 100. Description: optional. The description of the backend server. This parameter must be of the STRING type. The description can contain letters, digits, hyphens (-), forward slashes (/), periods (.),and underscores (_). Type: the type of backend server. This parameter must be of the STRING type. Valid values: ecs: an ECS instance. This is the default value. eni: an ENI. ServerIp: the IP address of the ECS instance or ENI. Examples: An ECS instance: `[{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }]` An ENI: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Port":"80","Description":"test-112" }]` An ENI with multiple IP addresses: `[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168..", "Port":"80","Description":"test-112" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166..", "Port":"80","Description":"test-113" }]`

Response parameters


Parameter	Type	Example	Description
VServerGroupId	String	rsp-cige6j****	The ID of the vServer group.
BackendServers	Array of BackendServer	N/A	The list of backend servers.
BackendServer	N/A	N/A	N/A
ServerId	String	i-bp1ge5hrp****	The ID of the ECS instance or ENI.
Port	Integer	70	The port that is used by the backend server.
Weight	Integer	100	The weight of the backend server.
Description	String	BackendServerDescription	The description of the backend server.
Type	String	ecs	The type of backend server. Valid values: ecs: an ECS instance. This is the default value. eni: an ENI.
RequestId	String	9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C	The ID of the request.

Examples

Sample requests

http(s)://[Endpoint]/?Action=ModifyVServerGroupBackendServers
&RegionId=cn-hangzhou
&VServerGroupId=rsp-cige6j****
&<Common request parameters>

Sample success responses

XML format

<ModifyVServerGroupBackendServersResponse>
  <VServerGroupId>rsp-cige6j****</VServerGroupId>
  <RequestId>9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C</RequestId>
  <BackendServers>
        <BackendServer>
              <Type>ecs</Type>
              <Description>BackendServerDescription </Description>
              <ServerId>i-bp1ge5hrp****</ServerId>
              <Port>70</Port>
              <Weight>100</Weight>
        </BackendServer>
  </BackendServers>
</ModifyVServerGroupBackendServersResponse>

JSON format

{
    "VServerGroupId": "rsp-cige6j****",
    "RequestId": "9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C",
    "BackendServers": {
        "BackendServer": {
            "Type": "ecs",
            "Description": "BackendServerDescription",
            "ServerId": "i-bp1ge5hrp****",
            "Port": 70,
            "Weight": 100
        }
    }
}

Error codes

For a list of error codes, visit the API Error Center.