Updated on 2025-09-22 GMT+08:00

Configuring a Health Check

Function

This API is used to configure a health check.

Constraints

This API has the following constraints:

  • The security groups must have rules that allow traffic to 100.125.0.0/16.

  • If you want to use UDP for health checks, ensure that the protocol of the backend server group is UDP.

Calling Method

For details, see Calling APIs.

URI

POST /v3/{project_id}/elb/healthmonitors

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

Request Parameters

Table 2 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

Table 3 Request body parameters

Parameter

Mandatory

Type

Description

healthmonitor

Yes

CreateHealthMonitorOption object

Definition: Specifies the request parameters for configuring a health check.

Constraints: N/A

Table 4 CreateHealthMonitorOption

Parameter

Mandatory

Type

Description

admin_state_up

No

Boolean

Definition: Specifies the administrative status of the health check.

Constraints: N/A

Range:

  • true: The health check function is enabled.

  • false: The health check function is disabled.

Default value: true

delay

Yes

Integer

Definition: Specifies the interval between health checks, in seconds.

Constraints: N/A

Range: 1 to 50

Default value: N/A

domain_name

No

String

Definition: Specifies the domain name that HTTP requests are sent to during the health check.

Constraints: This parameter is available only when type is set to HTTP or HTTPS.

Range: The value can contain only digits, letters, hyphens (-), and periods (.) and must start with a digit or letter.

Default value: The value is left blank by default, indicating that the virtual IP address of the load balancer is used as the destination address of HTTP requests.

expected_codes

No

String

Definition: Specifies the expected HTTP status code.

Constraints: This parameter will take effect only when type is set to HTTP, HTTPS or GRPC.

Range:

  • A specific value, for example, 200

  • A list of values that are separated with commas (,), for example, 200, 202

  • A value range, for example, 200-204

Default value: If type is set to GRPC, the default value is 0. If type is set to other protocols, the default value is 200.

http_method

No

String

Definition: Specifies the HTTP method.

Constraints: This parameter is available when type is set to HTTP or HTTPS.

Range: GET, HEAD, or POST

Default value: GET

max_retries

Yes

Integer

Definition: Specifies the number of consecutive health checks when the health check result of a backend server changes from OFFLINE to ONLINE.

Constraints: N/A

Range: 1 to 10

Default value: N/A

max_retries_down

No

Integer

Definition: Specifies the number of consecutive health checks when the health check result of a backend server changes from ONLINE to OFFLINE.

Constraints: N/A

Range: 1 to 10

Default value: N/A

monitor_port

No

Integer

Definition: Specifies the health check port.

Constraints:

  • This parameter is required if any_port_enable is set to true for the backend server group.

Range: 1 to 65535, or null (the port of a backend server will be used by default).

Default value: null

name

No

String

Definition: Specifies the health check name.

Constraints: N/A

Range: N/A

Default value: N/A

pool_id

Yes

String

Definition: Specifies the ID of the backend server group for which the health check is configured.

Constraints: N/A

Range: N/A

Default value: N/A

project_id

No

String

Specifies the project ID of the health check.

Constraints: N/A

Range: N/A

Default value: N/A

timeout

Yes

Integer

Definition: Specifies the maximum time required for waiting for a response from the health check, in seconds. It is recommended that you set the value less than that of parameter delay.

Constraints: N/A

Range: N/A

Default value: N/A

type

Yes

String

Definition: Specifies the health check protocol.

Constraints:

  • If the protocol of the backend server is QUIC, the value can only be UDP_CONNECT.

  • If the protocol of the backend server is UDP, the value can only be UDP_CONNECT.

  • If the protocol of the backend server is TCP, the value can only be TCP, HTTP, or HTTPS.

  • If the protocol of the backend server is HTTP, the value can only be TCP, HTTP, HTTPS, GRPC, or TLS.

  • If the protocol of the backend server is HTTPS, the value can only be TCP, HTTP, HTTPS, GRPC, or TLS.

  • If the protocol of the backend server is GRPC, the value can only be TCP, HTTP, HTTPS, GRPC, or TLS.

  • If the protocol of the backend server is TLS, the value can only be TCP, HTTP, HTTPS, GRPC, or TLS.

Range: The value can be TCP, UDP_CONNECT, HTTP, HTTPS, GRPC, or TLS.

Default value: N/A

url_path

No

String

Definition: Specifies the HTTP request path for the health check. The value must start with a slash (/), and the default value is /.

Constraints: This parameter is available only when type is set to HTTP or HTTPS.

Range: The value can contain letters, digits, hyphens (-), slashes (/), periods (.), percentage signs (%), question marks (?), pound signs (#), ampersand signs (&), and the extended character set: _;~!()*[]@$^:',+.

Default value: N/A

Response Parameters

Status code: 201

Table 5 Response body parameters

Parameter

Type

Description

request_id

String

Definition: Specifies the request ID.

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

healthmonitor

HealthMonitor object

Definition: Specifies the response parameters for configuring a health check.

Constraints: N/A

Table 6 HealthMonitor

Parameter

Type

Description

admin_state_up

Boolean

Definition: Specifies the administrative status of the health check.

Range:

  • true: The health check function is enabled.

  • false: The health check function is disabled.

delay

Integer

Definition: Specifies the interval between health checks, in seconds.

Range: 1 to 50

domain_name

String

Definition: Specifies the domain name that HTTP requests are sent to during the health check.

Range: The value can contain only digits, letters, hyphens (-), and periods (.) and must start with a digit or letter.

expected_codes

String

Definition: Specifies the expected HTTP status code.

Range:

  • A specific value, for example, 200

  • A list of values that are separated with commas (,), for example, 200, 202

  • A value range, for example, 200-204

http_method

String

Definition: Specifies the HTTP method.

Range: GET, HEAD, or POST

id

String

Specifies the health check ID.

Default value: N/A

max_retries

Integer

Definition: Specifies the number of consecutive health checks when the health check result of a backend server changes from OFFLINE to ONLINE.

Range: 1 to 10

max_retries_down

Integer

Definition: Specifies the number of consecutive health checks when the health check result of a backend server changes from ONLINE to OFFLINE.

Range: 1 to 10

monitor_port

Integer

Definition: Specifies the health check port.

Range: 1 to 65535, or null (the port of a backend server will be used by default).

name

String

Definition: Specifies the health check name.

Range: N/A

pools

Array of PoolRef objects

Specifies the IDs of the backend server groups for which the health check is configured. Only one ID will be returned.

Range: N/A

project_id

String

Definition: Specifies the project ID.

Range: N/A

timeout

Integer

Definition: Specifies the maximum time required for waiting for a response from the health check, in seconds.

Range: N/A

type

String

Definition: Specifies the health check protocol.

Range: The value can be TCP, UDP_CONNECT, HTTP, HTTPS, GRPC, or TLS.

url_path

String

Definition: Specifies the HTTP request path for the health check. The value must start with a slash (/), and the default value is /.

Range: The value can contain letters, digits, hyphens (-), slashes (/), periods (.), percentage signs (%), question marks (?), pound signs (#), ampersand signs (&), and the extended character set: _;~!()*[]@$^:',+.

created_at

String

Definition: Specifies the creation time.

Range: The value must be a UTC time in the format of yyyy-MM-dd'T'HH:mm:ss'Z'.

Note: This parameter 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

Definition: Specifies the update time.

Range: The value must be a UTC time in the format of yyyy-MM-dd'T'HH:mm:ss'Z'.

Note: This parameter will not be returned for resources associated with existing dedicated load balancers and for resources associated with existing and new shared load balancers.

Table 7 PoolRef

Parameter

Type

Description

id

String

Definition: Specifies the backend server group ID.

Range: N/A

Example Requests

Configuring a health check for an HTTP backend server group

POST https://{ELB_Endpoint}/v3/99a3fff0d03c428eac3678da6a7d0f24/elb/healthmonitors

{
  "healthmonitor" : {
    "name" : "My Healthmonitor",
    "max_retries" : 3,
    "pool_id" : "488acc50-6bcf-423d-8f0a-0f4184f5b8a0",
    "type" : "HTTP",
    "timeout" : 30,
    "delay" : 1
  }
}

Example Responses

Status code: 201

Successful request.

{
  "request_id" : "0e837340-f1bd-4037-8f61-9923d0f0b19e",
  "healthmonitor" : {
    "monitor_port" : null,
    "id" : "c2b210b2-60c4-449d-91e2-9e9ea1dd7441",
    "project_id" : "99a3fff0d03c428eac3678da6a7d0f24",
    "domain_name" : null,
    "name" : "My Healthmonitor",
    "delay" : 1,
    "max_retries" : 3,
    "pools" : [ {
      "id" : "488acc50-6bcf-423d-8f0a-0f4184f5b8a0"
    } ],
    "admin_state_up" : true,
    "timeout" : 30,
    "type" : "HTTP",
    "expected_codes" : "200",
    "url_path" : "/",
    "http_method" : "GET"
  }
}

SDK Sample Code

The SDK sample code is as follows.

Configuring a health check for an HTTP backend server group

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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 CreateHealthMonitorSolution {

    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();
        CreateHealthMonitorRequest request = new CreateHealthMonitorRequest();
        CreateHealthMonitorRequestBody body = new CreateHealthMonitorRequestBody();
        CreateHealthMonitorOption healthmonitorbody = new CreateHealthMonitorOption();
        healthmonitorbody.withDelay(1)
            .withMaxRetries(3)
            .withName("My Healthmonitor")
            .withPoolId("488acc50-6bcf-423d-8f0a-0f4184f5b8a0")
            .withTimeout(30)
            .withType("HTTP");
        body.withHealthmonitor(healthmonitorbody);
        request.withBody(body);
        try {
            CreateHealthMonitorResponse response = client.createHealthMonitor(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());
        }
    }
}

Configuring a health check for an HTTP backend server group

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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 = CreateHealthMonitorRequest()
        healthmonitorbody = CreateHealthMonitorOption(
            delay=1,
            max_retries=3,
            name="My Healthmonitor",
            pool_id="488acc50-6bcf-423d-8f0a-0f4184f5b8a0",
            timeout=30,
            type="HTTP"
        )
        request.body = CreateHealthMonitorRequestBody(
            healthmonitor=healthmonitorbody
        )
        response = client.create_health_monitor(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)

Configuring a health check for an HTTP backend server group

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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.CreateHealthMonitorRequest{}
	nameHealthmonitor:= "My Healthmonitor"
	healthmonitorbody := &model.CreateHealthMonitorOption{
		Delay: int32(1),
		MaxRetries: int32(3),
		Name: &nameHealthmonitor,
		PoolId: "488acc50-6bcf-423d-8f0a-0f4184f5b8a0",
		Timeout: int32(30),
		Type: "HTTP",
	}
	request.Body = &model.CreateHealthMonitorRequestBody{
		Healthmonitor: healthmonitorbody,
	}
	response, err := client.CreateHealthMonitor(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

201

Successful request.

Error Codes

See Error Codes.