Help Center> Elastic Load Balance> User Guide (ME-Abu Dhabi Region)> Health Check> Configuring a Health Check
Updated on 2022-01-25 GMT+08:00
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Configuring a Health Check

Scenarios

You can configure a health check when you add a listener. If you have no special requirements, retain the default settings. You can also disable the health check function or change the health check settings.

Function Description

  • The health check protocol and backend protocol are independent of each other. They can be the same or different from each other.
  • To reduce the CPU usage of backend servers, it is recommended that you use TCP for health checks. If you want to use HTTP as the health check protocol, you are advised to use static files to return the health check results.
  • You can increase the health check Interval to reduce the health check frequency.

Procedure

  1. Log in to the management console.
  2. In the upper left corner of the page, click and select the desired region and project.
  3. Click Service List. Under Network, click Elastic Load Balance.
  4. Locate the target load balancer and click its name.
  5. Click Backend Server Groups, locate the target backend server group, and click its name.
  6. In the Basic Information area, click Configure beside Health Check.
  7. In the Configure Health Check dialog box, enable or disable the health check function. Set the parameters by referring to Table 1.
    Table 1 Parameters for configuring a health check

    Parameter

    Description

    Example Value

    Enable Health Check

    Specifies whether to enable the health check function.

    N/A

    Protocol
    • Specifies the protocol used by the load balancer to perform health checks on backend servers. You can use either TCP or HTTP. A selected protocol cannot be changed.
    • If the frontend protocol is UDP, the health check protocol is UDP by default.

    HTTP

    Domain Name

    Specifies the domain name in the health check request. The domain name consists of digits, letters, hyphens (-), and periods (.), and must start with a digit or letter. This parameter is left blank by default and needs to be set only when the health check protocol is HTTP.

    www.elb.com

    Port

    Specifies the port used by the load balancer to perform health checks on backend servers. The port numbers range from 1 to 65535.

    NOTE:

    This parameter is optional. If no health check port is specified, the port of each backend server is used for health checks by default.

    80

    Interval (s)

    Specifies the maximum time between health checks in the unit of second.

    The value ranges from 1 to 50.

    5

    Timeout (s)

    Specifies the maximum time required for waiting for a response from the health check in the unit of second. The value ranges from 1 to 50.

    NOTE:

    The timeout must be less than or equal to the interval. Otherwise, the value set for the interval will be used as the timeout.

    3

    Check Path

    Specifies the health check URL, which is the destination on backend servers for health checks. This parameter is available only when Protocol is set to HTTP. The value can contain 1 to 80 characters and must start with a slash (/).

    /index.html

    Maximum Retries

    Specifies the maximum number of health check retries. The value ranges from 1 to 10.

    3
  8. Click OK.
Parent topic: Health Check