You can call this operation to specify weights of backend servers.

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 SetBackendServers

The operation that you want to perform.

Set the value to SetBackendServers.

LoadBalancerId String Yes lb-bp1qjwo61pqz3a******

The ID of the SLB instance that you want to query.
RegionId String Yes cn-hangzhou

The region ID of the SLB instance.
BackendServers String Yes [{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }]

The backend servers that you want to add to the SLB instance.

The value of this parameter is a JSON string with a JSON List structure. You can specify up to 20 elements in a list at a request.

  • ServerId: The instance ID of a backend server. This parameter is required and must be set to a string.
  • Port: The port number that is used by the backend server. This parameter must be set to an integer. Valid values: 1 to 65535.
  • Weight: The weight of the backend server. This parameter is required and must be set to an integer. Valid values: 0 to 100.
  • Description: The description of a backend server. This parameter is optional and must be set to a string. The description must be 1 to 80 characters in length and can contain letters, digits, hyphens (-), forward slashes (/), periods (.), and underscores (_).
  • Type: The instance type of the backend server. This parameter must be set to a string. Valid values:
    • ecs: ECS instance. This is the default value.
    • eni: Elastic Network Interface (ENI).
  • ServerIp: the IP address of an ECS instance or ENI instance.

Examples:

  • ECS instance: [{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }].
  • ENI: [{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168. **. **", "Port":"80","Description":"test-112" }]
  • 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" }]
Note
  • Only backend servers that are in the running state can be added to the SLB instance. You can add up to 20 backend servers in each call.
  • You can specify ENIs as the backend servers of only guaranteed-performance instances.

Response parameters

Parameter Type Example Description
LoadBalancerId String lb-bp1qjwo61pqz3a******

The ID of the SLB instance that you want to query.
BackendServers Array

The list of backend servers.
BackendServer
ServerId String i-xxxxxxxxx

The ID of the ECS instance.
Weight String 100

The weight of the backend server.
Description String The backend server.

The description of the backend server.
Type String ecs

The type of the backend server. Valid values:

  • ecs: ECS instance. This is the default value.
  • eni: ENI instance.
RequestId String 365F4154-92F6-4AE4-92F8-7FF34B540710

The ID of the request.

Examples

Sample requests

http(s)://[Endpoint]/? Action=SetBackendServers
&LoadBalancerId=lb-bp1qjwo61pqz3a******
&BackendServers=[{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs",  "Port":"80","Description":"test-112" }]
&<Common request parameters>

Sample success responses

XML format 

<SetBackendServersResponse>
      <RequestId>365F4154-92F6-4AE4-92F8-7FF34B540710</RequestId>
      <LoadBalancerId>lb-dhf13*******</LoadBalancerId>
      <BackendServers>
            <BackendServer>
                  <ServerId>eni-hg231**</ServerId>
                  <Weight>100</Weight>
                              <Type>eni</Type>
            </BackendServer>
            <BackendServer>
                  <ServerId>eni-hfhf***</ServerId>
                  <Weight>100</Weight>
                              <Type>eni</Type>
            </BackendServer>
      </BackendServers>
</SetBackendServersResponse>

JSON format 

{
    "RequestId": "365F4154-92F6-4AE4-92F8-7FF34B540710",
    "LoadBalancerId": "139a00604ad-cn-ea******",
    "BackendServers": {
      "BackendServer": [
        {
          "ServerId": "eni-hg231**",
          "Weight": "100",
          "Type": "eni"
        },
        {
          "ServerId": "eni-hhshhs****",
          "Weight": "100",
          "Type": "eni"
        }
      ]
    }
  }

Error codes

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