Help Center/ Elastic Load Balance/ User Guide/ User Guide for Dedicated Load Balancers/ Listener/ Application Listeners/ Adding an HTTP Listener
Updated on 2025-07-02 GMT+08:00
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Adding an HTTP Listener

Scenarios

You can add an HTTP listener if content identification is required. HTTP is a great fit for workloads such as web applications and mobile mini-games.

Constraints

  • If the listener protocol is HTTP, the backend protocol is HTTP by default and cannot be changed.
  • If you only select the network load balancing type for your dedicated load balancer, you cannot add HTTP listeners to this load balancer.

Procedure

  1. Go to the load balancer list page.
  2. On the displayed page, locate the load balancer and click its name.
  3. On the Listeners tab, click Add Listener. Configure the parameters based on Table 1.
    Table 1 Parameters for configuring an HTTP listener

    Parameter

    Description

    Name

    Specifies the listener name.

    Frontend Protocol

    Specifies the protocol that will be used by the load balancer to receive requests from clients.

    Select HTTP.

    Frontend Port

    Specifies the port that will be used by the load balancer to receive requests from clients.

    The port number ranges from 1 to 65535.

    Redirect

    Specifies whether to enable redirection.

    If you have both HTTPS and HTTP listeners, you can use this function to redirect requests from an HTTP listener to an HTTPS listener to ensure security.

    After a redirection is added for an HTTP listener, the backend server will return 301 Moved Permanently to the clients.

    Redirected To

    Specifies the HTTPS listener to which requests are redirected if Redirect is enabled.

    Access Control

    Specifies how access to the listener is controlled. For details, see What Is Access Control? The following options are available:

    • All IP addresses
    • Blacklist
    • Whitelist

    IP Address Group

    Specifies the IP address group associated with a whitelist or blacklist. If there is no IP address group, create one first. For more information, see IP Address Group.

    Transfer Client IP Address

    Specifies whether to transmit IP addresses of the clients to backend servers.

    This function is enabled for dedicated load balancers by default and cannot be disabled.

    Advanced Forwarding

    Specifies whether to enable advanced forwarding. This option allows you to configure advanced forwarding policies for HTTP or HTTPS listeners to forward requests to different backend server groups.

    For more information, see Advanced Forwarding.

    Advanced Settings (Optional)

    HTTP Headers
    You can enable the following options as needed.
    • Transfer headers:
      • Transfer Load Balancer EIP: transmits the EIP bound to the load balancer to backend servers through the X-Forwarded-ELB-IP header.
      • Transfer Listener Port Number: transmits the port number used by the listener to backend servers through the X-Forwarded-Port header.
      • Transfer Port Number in the Request: transmits the port number used by the client to backend servers through the X-Forwarded-For-Port header.
    • Rewrite headers:
      • Rewrite X-Forwarded-Host: rewrites the Host header in the request from the client into the X-Forwarded-Host header and transmits it to the backend servers.

    For details, see HTTP Headers.

    Idle Timeout (s)

    Specifies the length of time for a connection to keep alive, in seconds. If no request is received within this period, the load balancer closes the connection and establishes a new one with the client when the next request arrives.

    The idle timeout duration ranges from 0 to 4000.

    Request Timeout (s)

    Specifies the length of time (in seconds) that a load balancer is willing to wait for a client request to finish. The load balancer terminates the connection if a request takes too long to complete.

    The request timeout duration ranges from 1 to 300.

    Response Timeout (s)

    Specifies the length of time (in seconds) after which the load balancer sends a 504 Gateway Timeout error to the client if the load balancer receives no response from the backend server after routing a request to the backend server and receives no response after attempting to route the same request to other backend servers.

    If sticky session is enabled and the load balancer receives no response from the backend server within the response timeout duration, the load balancer returns a 504 Gateway Timeout error to the client directly.

    The response timeout duration ranges from 1 to 300.

    Description

    Provides supplementary information about the listener.

    You can enter a maximum of 255 characters.
  4. Click Next: Configure Request Routing Policy.
    1. You are advised to select an existing backend server group.
    2. You can also select Create new to create a backend server group.
      1. Configure the backend server group based on Table 3.
      2. Click Next: Add Backend Server. Add backend servers and configure a health check for the backend server group.

        For details about how to add backend servers, see Backend Server Overview. For the parameters required for configuring a health check, see Table 4.

  5. Click Next: Confirm.
  6. Confirm the configurations and click Submit.

Parent topic: Application Listeners