Queries the back-to-origin policies for the forwarding rule of a website.


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 DescribeL7RsPolicy

The operation that you want to perform. Set the value to DescribeL7RsPolicy.

Domain String Yes www.aliyun.com

The domain name of the website that you want to query.

Note A forwarding rule must be configured for the domain name. You can call the DescribeDomains operation to query the domain names for which the forwarding rules are created.
RegionId String No cn-hangzhou

The region ID of the instance. Valid values:

  • cn-hangzhou: mainland China, which indicates an Anti-DDoS Pro instance
  • ap-southeast-1: outside mainland China, which indicates an Anti-DDoS Premium instance
ResourceGroupId String No rg-acfm2pz25js****

The ID of the resource group to which the instance belongs in Resource Management. This parameter is empty by default, which indicates that the instance belongs to the default resource group.

For more information about resource groups, see Create a resource group.

RealServers.N RepeatList No 1.***. ***.1

The IP address of origin server N that you want to query.

All Alibaba Cloud API operations must include common request parameters. For more information about common request parameters, see Common parameters.

For more information about sample requests, see the "Examples" section of this topic.

Response parameters

Parameter Type Example Description
Attributes Array of AttributeItem

The details of the parameters for back-to-origin.

Attribute Struct

The parameter for back-to-origin.

Weight Integer 100

The weight of the server. This parameter takes effect only when ProxyMode is set to rr.

Valid values: 1 to 100. Default value: 100. A server with a higher weight receives more requests.

RealServer String 1.***. ***.1

The address of the origin server.

RsType Integer 0

The address type of the origin server. Valid values:

  • 0: IP address
  • 1: domain name
ProxyMode String rr

The load balancing policy for back-to-origin traffic. Valid values:

  • ip_hash: the IP hash algorithm. This algorithm is used to redirect the requests from the same IP address to the same origin server.
  • rr: the round-robin algorithm. This algorithm is used to redirect requests to origin servers in turn.
  • least_time: the least response time algorithm. This algorithm is used to minimize the latency when requests are forwarded from Anti-DDoS Pro or Anti-DDoS Premium instances to origin servers based on the intelligent DNS resolution feature.
RequestId String 9E7F6B2C-03F2-462F-9076-B782CF0DD502

The ID of the request.


Sample requests

&<Common request parameters>

Sample responses

XML format

            <RealServer>1. ***. ***.1</RealServer>
            <RealServer>2. ***. ***.2</RealServer>

JSON format

    "RequestId": "9E7F6B2C-03F2-462F-9076-B782CF0DD502",
    "Attributes": [
            "RealServer": "1. ***. ***.1",
            "Attribute": {
                "Weight": 100
            "RealServer": "2. ***. ***.2",
            "Attribute": {
                "Weight": 100
    "ProxyMode": "rr"

Error codes

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