Help Center/ Elastic Load Balance/ API Reference/ APIs (V3)/ Load Balancer/ Querying the Ports on the Downstream Subnet Used by a Load Balancer
Updated on 2025-09-22 GMT+08:00

Querying the Ports on the Downstream Subnet Used by a Load Balancer

Function

This API is used to query the ports and IP addresses on the downstream subnet used by a load balancer to forward requests within a private network.

Calling Method

For details, see Calling APIs.

URI

GET /v3/{project_id}/elb/loadbalancers/{loadbalancer_id}/local-ports

Table 1 Path Parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

Definition: Specifies the project ID. For details about how to obtain a project ID, see Obtaining a Project ID.

Constraints: N/A

Range: The value can contain a maximum of 32 characters, including digits and lowercase letters.

Default value: N/A

loadbalancer_id

Yes

String

Definition: Specifies the load balancer ID.

Constraints: N/A

Range: N/A

Default value: N/A

Table 2 Query Parameters

Parameter

Mandatory

Type

Description

port_id

No

Array of strings

Definition: Specifies the ID of the port used by the load balancer.

Multiple IDs can be used for query in the format of port_id=xxx&port_id=xxx.

ip_address

No

Array of strings

Definition: Specifies the private IPv4 address used by the load balancer.

Constraints: N/A

Range: N/A

Default value: N/A

Multiple IP addresses can be used for query in the format of ip_address=xxx&ip_address=xxx.

ipv6_address

No

Array of strings

Definition: Specifies the IPv6 address used by the load balancer.

Constraints: N/A

Range: N/A

Default value: N/A

Multiple IPv6 addresses can be used for query in the format of ipv6_address=xxx&ipv6_address=xxx.

type

No

Array of strings

Definition: Specifies the port type.

Constraints: N/A

Range: N/A

Default value: N/A

Multiple types can be used for query in the format of type=xxx&type=xxx.

virsubnet_id

No

Array of strings

Definition: Specifies the network ID of the downstream subnet where the port is located.

Constraints: N/A

Range: N/A

Default value: N/A

Multiple IDs can be used for query in the format of virsubnet_id=xxx&virsubnet_id=xxx.

Request Parameters

Table 3 Request header parameters

Parameter

Mandatory

Type

Description

X-Auth-Token

Yes

String

Definition: Specifies the token used for IAM authentication.

Constraints: N/A

Range: N/A

Default value: N/A

Response Parameters

Status code: 200

Table 4 Response body parameters

Parameter

Type

Description

ports

Array of LocalPort objects

Definition: Specifies the ports used by the load balancer.

request_id

String

Definition: Specifies the request ID.

Range: The value is automatically generated, and can contain characters including digits, lowercase letters, and hyphens (-).

Table 5 LocalPort

Parameter

Type

Description

port_id

String

Definition: Specifies the ID of the port used by the load balancer.

Range: N/A

ip_address

String

Definition: Specifies the private IPv4 address used by the load balancer.

Range: N/A

ipv6_address

String

Definition: Specifies the IPv6 address used by the load balancer.

Range: N/A

type

String

Definition: Specifies the port type.

Range:

  • l4_hc: port used for health checks during Layer 4 traffic forwarding using DNAT.

  • l4: port used for Layer 4 health checks and traffic forwarding using FullNAT.

  • l7: port used for Layer 7 health checks and service forwarding.

virsubnet_id

String

Definition: Specifies the network ID of the downstream subnet where the port is located.

Range: N/A

Example Requests

Querying the ports used by a load balancer

GET https://{ELB_Endpoint}/v3/{project_id}/elb/loadbalancers/38278031-cfca-44be-81be-a412f618773b/local-ports

Example Responses

Status code: 200

Successful operation

{
  "ports" : [ {
    "port_id" : "b796e55e-988a-429e-a132-9245beb046e5",
    "ip_address" : "192.168.1.2",
    "ipv6_address" : "2420:2023:410:151:49c:7163:342a:3e3",
    "type" : "l4_hc",
    "virsubnet_id" : "4507af92-719f-4878-9394-6a6a6ba1dcbb"
  } ]
}

SDK Sample Code

The SDK sample code is as follows.

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package com.huaweicloud.sdk.test;

import com.huaweicloud.sdk.core.auth.ICredential;
import com.huaweicloud.sdk.core.auth.BasicCredentials;
import com.huaweicloud.sdk.core.exception.ConnectionException;
import com.huaweicloud.sdk.core.exception.RequestTimeoutException;
import com.huaweicloud.sdk.core.exception.ServiceResponseException;
import com.huaweicloud.sdk.elb.v3.region.ElbRegion;
import com.huaweicloud.sdk.elb.v3.*;
import com.huaweicloud.sdk.elb.v3.model.*;


public class ShowLoadBalancerPortsSolution {

    public static void main(String[] args) {
        // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
        // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
        String ak = System.getenv("CLOUD_SDK_AK");
        String sk = System.getenv("CLOUD_SDK_SK");
        String projectId = "{project_id}";

        ICredential auth = new BasicCredentials()
                .withProjectId(projectId)
                .withAk(ak)
                .withSk(sk);

        ElbClient client = ElbClient.newBuilder()
                .withCredential(auth)
                .withRegion(ElbRegion.valueOf("<YOUR REGION>"))
                .build();
        ShowLoadBalancerPortsRequest request = new ShowLoadBalancerPortsRequest();
        request.withLoadbalancerId("{loadbalancer_id}");
        try {
            ShowLoadBalancerPortsResponse response = client.showLoadBalancerPorts(request);
            System.out.println(response.toString());
        } catch (ConnectionException e) {
            e.printStackTrace();
        } catch (RequestTimeoutException e) {
            e.printStackTrace();
        } catch (ServiceResponseException e) {
            e.printStackTrace();
            System.out.println(e.getHttpStatusCode());
            System.out.println(e.getRequestId());
            System.out.println(e.getErrorCode());
            System.out.println(e.getErrorMsg());
        }
    }
}
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# coding: utf-8

import os
from huaweicloudsdkcore.auth.credentials import BasicCredentials
from huaweicloudsdkelb.v3.region.elb_region import ElbRegion
from huaweicloudsdkcore.exceptions import exceptions
from huaweicloudsdkelb.v3 import *

if __name__ == "__main__":
    # The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    # In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak = os.environ["CLOUD_SDK_AK"]
    sk = os.environ["CLOUD_SDK_SK"]
    projectId = "{project_id}"

    credentials = BasicCredentials(ak, sk, projectId)

    client = ElbClient.new_builder() \
        .with_credentials(credentials) \
        .with_region(ElbRegion.value_of("<YOUR REGION>")) \
        .build()

    try:
        request = ShowLoadBalancerPortsRequest()
        request.loadbalancer_id = "{loadbalancer_id}"
        response = client.show_load_balancer_ports(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)
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package main

import (
	"fmt"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic"
    elb "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3/model"
    region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3/region"
)

func main() {
    // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak := os.Getenv("CLOUD_SDK_AK")
    sk := os.Getenv("CLOUD_SDK_SK")
    projectId := "{project_id}"

    auth := basic.NewCredentialsBuilder().
        WithAk(ak).
        WithSk(sk).
        WithProjectId(projectId).
        Build()

    client := elb.NewElbClient(
        elb.ElbClientBuilder().
            WithRegion(region.ValueOf("<YOUR REGION>")).
            WithCredential(auth).
            Build())

    request := &model.ShowLoadBalancerPortsRequest{}
	request.LoadbalancerId = "{loadbalancer_id}"
	response, err := client.ShowLoadBalancerPorts(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

For SDK sample code of more programming languages, see the Sample Code tab in API Explorer. SDK sample code can be automatically generated.

Status Codes

Status Code

Description

200

Successful operation

Error Codes

See Error Codes.