Querying Backend Server Groups

Function

This API is used to query all backend server groups.

Constraints

This API has the following constraints:

Parameters marker, limit, and page_reverse are used for pagination query.
Parameters marker and page_reverse take effect only when they are used together with parameter limit.

Calling Method

For details, see Calling APIs.

URI

GET /v3/{project_id}/elb/pools

**Table 1** Path Parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Specifies the project ID.

**Table 2** Query Parameters
Parameter	Mandatory	Type	Description
marker	No	String	Specifies the ID of the last record on the previous page. Note: This parameter must be used together with limit. If this parameter is not specified, the first page will be queried. This parameter cannot be left blank or set to an invalid ID.
limit	No	Integer	Specifies the number of records on each page. The value ranges from 0 to 2,000, and the default value is 2,000.
page_reverse	No	Boolean	Specifies whether to use reverse query. Values: true: Query the previous page. false (default): Query the next page. Note: This parameter must be used together with limit. If page_reverse is set to true and you want to query the previous page, set the value of marker to the value of previous_marker.
description	No	Array of strings	Provides supplementary information about the backend server group. Multiple descriptions can be queried in the format of description=xxx&description=xxx.
admin_state_up	No	Boolean	Specifies the administrative status of the backend server group.
healthmonitor_id	No	Array of strings	Specifies the ID of the health check configured for the backend server group. Multiple IDs can be queried in the format of healthmonitor_id=xxx&healthmonitor_id=xxx.
id	No	Array of strings	Specifies the ID of the backend server group. Multiple IDs can be queried in the format of id=xxx&id=xxx.
name	No	Array of strings	Specifies the backend server group name. Multiple names can be queried in the format of name=xxx&name=xxx.
loadbalancer_id	No	Array of strings	Specifies the ID of the load balancer with which the backend server group is associated. Multiple IDs can be queried in the format of loadbalancer_id=xxx&loadbalancer_id=xxx.
protocol	No	Array of strings	Specifies the protocol used by the backend server group to receive requests from the load balancer. The value can be TCP, UDP, TLS, HTTP, HTTPS, gRPC, or QUIC. Multiple protocols can be queried in the format of protocol=xxx&protocol=xxx.
lb_algorithm	No	Array of strings	Specifies the load balancing algorithm used by the load balancer to route requests to backend servers in the associated backend server group. The value can be one of the following: ROUND_ROBIN: weighted round robin LEAST_CONNECTIONS: weighted least connections SOURCE_IP: source IP hash QUIC_CID: connection ID Multiple algorithms can be queried in the format of lb_algorithm=xxx&lb_algorithm=xxx.
enterprise_project_id	No	Array of strings	Specifies the enterprise project ID. If this parameter is not passed, resources in the default enterprise project are queried, and authentication is performed based on the default enterprise project. If this parameter is passed, its value can be the ID of an existing enterprise project (resources in the specific enterprise project are required) or all_granted_eps (resources in all enterprise projects are queried). Multiple IDs can be queried in the format of enterprise_project_id=xxx&enterprise_project_id=xxx.
ip_version	No	Array of strings	Specifies the IP address version supported by the backend server group. Multiple versions can be queried in the format of ip_version=xxx&ip_version=xxx.
member_address	No	Array of strings	Specifies the private IP address bound to the backend server. This is a query parameter and will not be included in the response. Multiple IP addresses can be queried in the format of member_address=xxx&member_address=xxx.
member_device_id	No	Array of strings	Specifies the ID of the ECS that serves as a backend server. This parameter is used only as a query condition and is not included in the response. Multiple IDs can be queried in the format of member_device_id=xxx&member_device_id=xxx.
member_deletion_protection_enable	No	Boolean	Specifies whether to enable removal protection on backend servers. true: Enable removal protection. false: Disable removal protection. All backend servers will be queried if this parameter is not passed.
listener_id	No	Array of strings	Specifies the IDs of the associated listeners, including the listeners associated through forwarding policies. Multiple IDs can be queried in the format of listener_id=xxx&listener_id=xxx.
member_instance_id	No	Array of strings	Specifies the backend server ID. This parameter is used only as a query condition and is not included in the response. Multiple IDs can be queried in the format of member_instance_id=xxx&member_instance_id=xxx.
vpc_id	No	Array of strings	Specifies the ID of the VPC where the backend server group works.
type	No	Array of strings	Specifies the type of the backend server group. The value can be: instance: Any type of backend servers can be added. vpc_id is mandatory. ip: Only IP as backend servers can be added. vpc_id cannot be specified. "": Any type of backend servers can be added.
any_port_enable	No	Boolean	Specifies whether to enable any_port_enable for a backend server group. If this option is enabled, the listener routes the requests to the backend server over the same port as the frontend port. The value can be: false: Disable this option. true: Enable this option.

Request Parameters

**Table 3** Request header parameters
Parameter	Mandatory	Type	Description
X-Auth-Token	Yes	String	Specifies the token used for IAM authentication.

Response Parameters

Status code: 200

**Table 4** Response body parameters
Parameter	Type	Description
request_id	String	Specifies the request ID. Note: The value is automatically generated.
page_info	PageInfo object	Shows pagination information.
pools	Array of Pool objects	Lists the backend server groups.

**Table 5** PageInfo
Parameter	Type	Description
previous_marker	String	Specifies the ID of the first record in the pagination query result.
next_marker	String	Specifies the ID of the last record in the pagination query result.
current_count	Integer	Specifies the number of records.

**Table 6** Pool
Parameter	Type	Description
admin_state_up	Boolean	Specifies the administrative status of the backend server group.
description	String	Provides supplementary information about the backend server group.
healthmonitor_id	String	Specifies the ID of the health check configured for the backend server group.
id	String	Specifies the backend server group ID.
lb_algorithm	String	Specifies the load balancing algorithm used by the load balancer to route requests to backend servers in the associated backend server group. The value can be one of the following: ROUND_ROBIN: weighted round robin LEAST_CONNECTIONS: weighted least connections SOURCE_IP: source IP hash QUIC_CID: connection ID Notes and constraints: If the value is SOURCE_IP or QUIC_CID, the weight parameter will not take effect for backend servers. QUIC_CID is supported only when the protocol of the backend server group is QUIC.
listeners	Array of ListenerRef objects	Specifies the IDs of the listeners with which the backend server group is associated.
loadbalancers	Array of LoadBalancerRef objects	Specifies the IDs of the load balancers with which the backend server group is associated.
members	Array of MemberRef objects	Specifies the IDs of the backend servers in the backend server group.
name	String	Specifies the backend server group name.
project_id	String	Specifies the project ID.
protocol	String	Specifies the protocol used by the backend server group to receive requests. The value can be TCP, UDP, TLS, HTTP, HTTPS, gRPC, or QUIC. Notes and constraints: If the listener's protocol is UDP, the protocol of the backend server group must be UDPor QUIC. If the listener's protocol is TCP, the protocol of the backend server group must be TCP. If the listener's protocol is HTTP, the protocol of the backend server group must be HTTP. If the listener's protocol is HTTPS, the protocol of the backend server group can be HTTP, HTTPS, or gRPC. If the listener's protocol is TERMINATED_HTTPS, the protocol of the backend server group must be HTTP. If the listener's protocol is QUIC, the protocol of the backend server group can be HTTP, HTTPS, or gRPC. If the listener's protocol is TLS, the protocol of the backend server group can be TLS or TCP. If protocol of the backend server group is QUIC, session_persistence must be set to true, with type set to SOURCE_IP. If protocol of the backend server group is gRPC, http2_enable of the listener must be set to true. If protocol of the backend server group is TCP, the ip_version must be set to v4.
session_persistence	SessionPersistence object	Specifies the sticky session.
ip_version	String	Specifies the IP address version supported by the backend server group. Shared load balancers: The value is fixed at v4. Dedicated load balancers: The value can be dualstack or v4. If the protocol of the backend server group is TCP, UDP, or QUIC, the value is dualstack. If the protocol of the backend server group is HTTP or HTTPS, the value is v4.
slow_start	SlowStart object	Specifies slow start details. After you enable slow start, new backend servers added to the backend server group are warmed up, and the number of requests they can receive increases linearly during the configured slow start duration. This parameter can be used when the protocol of the backend server group is HTTP or HTTPS. An error will be returned if the protocol is not HTTP or HTTPS.
member_deletion_protection_enable	Boolean	Specifies whether to enable removal protection. The value can be: true: Enable removal protection. false: Disable removal protection. NOTE: Disable removal protection for all your resources before deleting your account.
created_at	String	Specifies the time when the forwarding policy was added. The format is yyyy-MM-dd'T'HH:mm:ss'Z' (UTC time). This is a new field in this version, and it will not be returned for resources associated with existing dedicated load balancers and for resources associated with existing and new shared load balancers.
updated_at	String	Specifies the time when the forwarding policy was updated. The format is yyyy-MM-dd'T'HH:mm:ss'Z' (UTC time). This is a new field in this version, and it will not be returned for resources associated with existing dedicated load balancers and for resources associated with existing and new shared load balancers.
vpc_id	String	Specifies the ID of the VPC where the backend server group works.
type	String	Specifies the type of the backend server group. The value can be: instance: Any type of backend servers can be added. vpc_id is mandatory. ip: Only IP as backend servers can be added. vpc_id cannot be specified. "": Any type of backend servers can be added.
protection_status	String	Specifies the protection status. The value can be: nonProtection (default): The resource is not protected against being modified by accident. consoleProtection: The resource is protected against being modified by accident.
protection_reason	String	Specifies why the modification protection function is enabled. Notes and constraints: This parameter is valid only when protection_status is set to consoleProtection.
any_port_enable	Boolean	Specifies whether to enable any_port_enable for a backend server group. If this option is enabled, the listener routes the requests to the backend server over the same port as the frontend port. If this option is disabled, the listener routes the requests over the port specified by protocol_port. The value can be: false: Disable this option. true: Enable this option. Notes and constraints: This option is available only for TCP, UDP, or QUIC backend server groups.
enterprise_project_id	String	Specifies the enterprise project ID of the IP address group.

**Table 7** ListenerRef
Parameter	Type	Description
id	String	Specifies the listener ID.

**Table 8** LoadBalancerRef
Parameter	Type	Description
id	String	Specifies the load balancer ID.

**Table 9** MemberRef
Parameter	Type	Description
id	String	Specifies the backend server ID.

**Table 10** SessionPersistence
Parameter	Type	Description
cookie_name	String	Specifies the cookie name. Notes and constraints: This parameter will take effect only when type is set to APP_COOKIE. Otherwise, an error will be returned. Value ranges: For shared load balancers, the name can contain a maximum of 64 characters, including letters, digits, underscores (_), and hyphens (-). For dedicated load balancers, the name can contain a maximum of 255 characters, including letters, digits, underscores (_), hyphens (-), and periods (.).
type	String	Specifies the sticky session type. The value can be SOURCE_IP, HTTP_COOKIE, or APP_COOKIE. Notes and constraints: If the protocol of the backend server group is TCP or UDP, only SOURCE_IP takes effect. For dedicated load balancers, if the protocol of the backend server group is HTTP or HTTPS, the value can only be HTTP_COOKIE. For shared load balancers, if the protocol of the backend server group is HTTP or HTTPS, the value can be HTTP_COOKIE or APP_COOKIE. If the backend server group protocol is QUIC, sticky session must be enabled with type set to SOURCE_IP.
persistence_timeout	Integer	Specifies the stickiness duration, in minutes. This parameter will not take effect when type is set to APP_COOKIE. Value ranges: If the protocol of the backend server group is TCP, UDP, or QUIC, the value ranges from 1 to 60, and the default value is 1. If the protocol of the backend server group is HTTP or HTTPS, the value ranges from 1 to 1440, and the default value is 1440.

**Table 11** SlowStart
Parameter	Type	Description
enable	Boolean	Specifies whether to enable slow start. The value can be: true: Enable slow start. false (default): Disable slow start.
duration	Integer	Specifies the slow start duration, in seconds. The value ranges from 30 to 1200, and the default value is 30.

Example Requests

Querying backend server groups

GET https://{ELB_Endpoint}/v3/99a3fff0d03c428eac3678da6a7d0f24/elb/pools?limit=2

Example Responses

Status code: 200

Successful request.

{
  "pools" : [ {
    "lb_algorithm" : "ROUND_ROBIN",
    "protocol" : "HTTP",
    "type" : "",
    "vpc_id" : "",
    "description" : "",
    "admin_state_up" : true,
    "member_deletion_protection_enable" : false,
    "loadbalancers" : [ {
      "id" : "309a0f61-0b62-45f2-97d1-742f3434338e"
    } ],
    "project_id" : "99a3fff0d03c428eac3678da6a7d0f24",
    "session_persistence" : {
      "cookie_name" : "my_cookie",
      "type" : "APP_COOKIE",
      "persistence_timeout" : 1
    },
    "healthmonitor_id" : "",
    "listeners" : [ ],
    "members" : [ ],
    "id" : "73bd4fe0-ffbb-4b56-aab4-4f26ddf7a103",
    "name" : "",
    "ip_version" : "v4",
    "pool_health" : {
      "minimum_healthy_member_count" : 0
    }
  }, {
    "lb_algorithm" : "SOURCE_IP",
    "protocol" : "TCP",
    "description" : "",
    "admin_state_up" : true,
    "member_deletion_protection_enable" : false,
    "loadbalancers" : [ {
      "id" : "d9763e59-64b7-4e93-aec7-0ff7881ef9bc"
    } ],
    "project_id" : "99a3fff0d03c428eac3678da6a7d0f24",
    "session_persistence" : {
      "cookie_name" : "",
      "type" : "SOURCE_IP",
      "persistence_timeout" : 1
    },
    "healthmonitor_id" : "",
    "listeners" : [ {
      "id" : "8d21db6f-b475-429e-a9cb-90439b0413b2"
    } ],
    "members" : [ ],
    "id" : "74db02d1-5711-4c77-b383-a450e2b93142",
    "name" : "pool_tcp_001",
    "ip_version" : "dualstack",
    "pool_health" : {
      "minimum_healthy_member_count" : 0
    }
  } ],
  "page_info" : {
    "next_marker" : "74db02d1-5711-4c77-b383-a450e2b93142",
    "previous_marker" : "73bd4fe0-ffbb-4b56-aab4-4f26ddf7a103",
    "current_count" : 2
  },
  "request_id" : "a1a7e852-1928-48f7-bbc9-ca8469898713"
}

SDK Sample Code

The SDK sample code is as follows.

      
       
         
         
           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 ListPoolsSolution {

    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();
        ListPoolsRequest request = new ListPoolsRequest();
        try {
            ListPoolsResponse response = client.listPools(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());
        }
    }
}

          

        

      
     

      
       
         
         
           # 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 = ListPoolsRequest()
        response = client.list_pools(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)

          

        

      
     

      
       
         
         
           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.ListPoolsRequest{}
	response, err := client.ListPools(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

          

        

      
     