Help Center/ API Gateway/ Best Practices/ API Openness/ Exposing Backend Services Across VPCs Using a Dedicated Gateway/ Implementation Procedure
Updated on 2025-01-16 GMT+08:00
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Implementation Procedure

Creating a VPC

  1. Log in to the network console.
  2. In the navigation pane, choose Virtual Private Cloud > My VPCs.
  3. On the Virtual Private Cloud page, click Create VPC, and configure the parameters by referring to Table 1 and Table 2. For details, see sections "Creating a VPC" and "Creating a Subnet for the VPC" in the Virtual Private Cloud User Guide.

    Table 1 Configuration information

    Parameter

    Description

    Region

    Select a region.

    Name

    Enter VPC1. This VPC will be used to run a gateway.

    Enterprise Project

    Select default.

    Name

    A subnet is automatically created when you create a VPC.
    Table 2 VPC CIDR block planning

    VPC 1

    VPC of APIG

    VPC 2

    10.X

    172.31.0.0/16

    Must be different from VPC 1 and the VPC of the gateway.

    172.X

    192.168.0.0/16

    192.X

    172.31.0.0/16

  4. Click Create Now.
  5. Repeat 3 to 4 to create VPC2 for running your backend service.

Creating a Gateway

  1. Go to the APIG console.
  2. In the navigation pane, choose Gateways.
  3. Click Buy Gateway.

    Table 3 Gateway information

    Parameter

    Description

    Billing Mode

    Billing mode of the gateway. Select Pay-per-use.

    Region

    Select the region where the gateway is located. It must be the same as the region of VPC 1.

    AZ

    The AZ where the gateway is located. Select AZ1.

    Gateway Name

    Name of the gateway.

    Edition

    Select Professional. The edition cannot be changed after the gateway is created.

    Scheduled Maintenance

    Select a time period when the gateway can be maintained by technical support engineers. A period with low service traffic is recommended. For this example, retain the default value 22:00:00---02:00:00.

    Enterprise Project

    Select the enterprise project to which the gateway belongs. For this example, retain the default value default.

    Network

    Select VPC 1 and a subnet.

    Security Group

    Click Manage Security Groups and create a security group. Ensure that you have selected default for Enterprise Project.

    Description

    Description of the gateway.

  4. Click Next.
  5. If the gateway configurations are correct, read and confirm your acceptance of the customer agreement and privacy statement, and create the instance.

Creating a Load Balancer

  1. Return to the network console.
  2. In the navigation pane, choose Elastic Load Balance > Load Balancers.
  3. Click Buy Elastic Load Balancer.
  4. Configure the load balancer information. For details, see section Load Balancer in the Elastic Load Balance User Guide.

    Table 4 Load balancer parameters

    Parameter

    Description

    Type

    Type of the load balancer.

    Billing Mode

    By default, Pay-per-use is selected.

    Region

    Select the region where the load balancer is located. It must be the same as the region of VPC 2.

    AZ

    The AZ where the load balancer is located. Select AZ1.

    Name

    Name of the load balancer.

    Enterprise Project

    Select default.

    Specification

    Select Fixed – Application load balancing (HTTP/HTTPS) and Network load balancing (TCP/UDP) by default.

    Network Type

    Select Private IPv4 network by default.

    VPC

    Select VPC 2.

    Frontend Subnet

    Select a subnet.

  5. Click Next.
  6. Confirm the configuration and click Submit.
  7. Add a listener.

    1. Click the name of the load balancer. On the Listeners tab page, click Add Listener.
    2. Configure the listener name, frontend protocol, and port, and click Next.
    3. Configure the backend server group name, backend protocol, and load balancing algorithm. Then click Next.
    4. Add backend servers and click Next.
    5. Click Submit. The following figure shows the configuration.
    Figure 1 Viewing the basic information and backend server group of the listener

Creating a VPC Peering Connection

  1. In the navigation pane, choose Virtual Private Cloud > VPC Peering Connections.
  2. Click Create VPC Peering Connection and configure the parameters.

    Table 5 Configuring a VPC peering connection

    Parameter

    Description

    Region

    Select a region that is the same as the region of VPC 1.

    VPC Peering Connection Name

    Name of the VPC peering connection.

    Local VPC

    Select VPC 1.

    Account

    By default, My account is selected.

    Peer Project

    Select a project

    Peer VPC

    Select VPC 2.

  3. Click OK.
  4. In the displayed dialog box, click Add Now to go to the VPC peering connection details page.
  5. On the Associated Routes area, click Add Route.

    1. In the displayed dialog box, enter the route information.
      Table 6 Local and peer routing information

      Parameter

      Description

      Local routes

      VPC

      Select VPC 1.

      Route Table

      VPC 1 route table

      Destination

      Enter the service address displayed on the details page of the load balancer.

      Peer routes

      VPC

      Select VPC 2.

      Route Table

      VPC 2 route table

      Destination

      Enter the private outbound address displayed on the details page of the dedicated gateway.
    2. Click OK.

Configuring a Route

  1. Return to the APIG console.
  2. In the navigation pane, choose Gateways.
  3. Click the name of the created dedicated gateway or click Access Console.
  4. Click Change in the Routes area, enter the IPv4 CIDR block of VPC 2 where the load balancer you created is located.
  5. Click Save.

Creating an API

  1. On the APIG console, choose API Management > APIs, and click Create API > Create API.
  2. Configure the frontend information and click Next.

    Table 7 Frontend configuration

    Parameter

    Description

    API Name

    Enter an API name.

    Group

    The default option is DEFAULT.

    URL
    • Method: Request method of the API. Set this parameter to GET.
    • Protocol: Request protocol of the API. Set this parameter to HTTPS.
    • Subdomain Name: The system automatically allocates a subdomain name to each API group for internal testing. The subdomain name can be accessed 1,000 times a day.
    • Path: Path for requesting the API.

    Gateway Response

    Select a response to be displayed if the gateway fails to process an API request.

    The default gateway response is default.

    Authentication Mode

    API authentication mode. Select None. (None: Not recommended for actual services. All users will be granted access to the API.)

  3. Configure the backend information and click Next.

    Table 8 Parameters for defining an HTTP/HTTPS backend service

    Parameter

    Description

    Load Balance Channel

    Determine whether the backend service will be accessed using a load balance channel. For this example, select Skip.

    URL
    • Method: Request method of the API. Set this parameter to GET.
    • Protocol: Set this parameter to HTTP.
    • Backend Address: Enter the service address of the load balancer you created.
    • Path: Path of the backend service.

  4. Define the response and click Finish.

Creating an ECS

  1. Log in to the cloud server console.
  2. Click Buy ECS.
  3. Configure the basic settings and click Next: Configure Network.

    Table 9 Basic settings

    Parameter

    Description

    Billing Mode

    Select Pay-per-use.

    Region

    Select the region where the ECS is located. It must be the same as the region of VPC 2.

    AZ

    Select the AZ where the ECS is located.

    CPU Architecture

    The default option is x86.

    Specifications

    Select specifications that match your service planning.

    Image

    Select an image that matches your service planning.

    VPC

    Select VPC 2.

    Primary NIC

    Select the subnet of the created VPC.

    Security Group

    Select the security group created for the dedicated gateway.

    EIP

    Select Not required.

    ECS Name

    Enter an ECS name.

    Login Mode

    Credential for logging in to the ECS. The default option is Password.

    Username

    The default user is root.

    Password

    Set a password for logging in to the ECS.

    Confirm Password

    Enter the password again.

    Enterprise Project

    Select "default".

  4. Read and confirm your acceptance of the agreement. Then click Create.

Debugging the API

  1. In the load balancer listener details, click View/Add Backend Server.
  2. On the Backend Servers page, add the created ECS.
  3. Go to the API Management > APIs page of the dedicated gateway, and choose More > Debug in the row that contains the API you created.
  4. Enter the request parameters and click Debug.

    If the status code is 200, the debugging is successful. Otherwise, rectify the fault by following the instructions provided in Error Codes.