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Test Access Control ports from the local network using Telnet with Microsoft Windows

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The Telnet client allows you to quickly determine if remote TCP ports are accessible.

Prepare a Microsoft Windows computer to test for port communication

A Microsoft Windows computer can be prepared to test for port communication using a command prompt or using the Control Panel.

  1. Open Control Panel.
  2. Click Programs.
  3. Click to enable Turn Windows features on or off.
  4. Enable Telnet Client.
  5. Click OK, then click Restart.

Important: The provided steps require Windows 8 or above.

  1. Open a Command Prompt window as an Administrator.
    1. Use the search feature in your taskbar and search for CMD.
    2. Right-click on Command Prompt, then click Run as administrator.
  2. In the Command Prompt window, copy, paste, and run the following command: Dism /Online /Enable-feature /FeatureName:TelnetClient

    Test Ports from Local Network1.PNG
     

  3. If successful, you should see the confirmation pictured above. If the result returned states Elevated permissions are required to run DISM, retry step 1.

    Note: Once enabled, you should not need to perform steps 1-3 again.

  4. Telnet client is now permanently installed on the computer and port communication can now be tested.

How to test TCP port communication with Microsoft Windows:

  1. Temporarily disconnect the device (e.g., Access Controller, video device, etc.) from its current network switch port and plug the computer you will be testing with into the same port.
  2. Open a Command Prompt window.
    1. Use the search feature in your taskbar and search for CMD.
    2. Click Command Prompt to open the window.
  3. In the Command Prompt window:
    • For Mercury boards, enter telnet mercury.g4c5j.com 7001.
    • For Aero boards, enter telnet mercury.g4c5j.com 8001.

      Test Ports from Local Network2.PNG
  4. Press Enter.
  5. If the screen clears and you see a blank Command Prompt screen or random characters, this indicates you are able to successfully reach the TCP port:
    • Successful result possibility 1:

      Test Ports from Local Network3.PNG
       
    • Successful result possibility 2:

      Test Ports from Local Network4.PNG

How to determine a potential TCP port issue:

If you see the following results, there may be a firewall rule in place preventing communication to the desired TCP ports:

Test Ports from Local Network5.PNG

Resolving port blocking issues

Protocols/ports required are being blocked by a network firewall

If it is determined that a firewall is in place, contact the network IT Admin and provide them with the following information based on the Access Control hardware series used:

Access Control (Mercury Series)

Request that access is opened for outbound communication to the following:

Access Control (HID Aero Series)

Request that access is opened for outbound communication to the following:

Additional considerations

Along with the port request, it is also recommended to provide the network IT Admin with the following information as it may help expedite the process:

  • Screenshots of your Telnet test results
  • A screenshot of the output from the following command (executed in a Command Prompt window) so that they are able to see what network information was assigned to your computer during the test: ipconfig /all
  • Information about the switch and switch port you are plugged into
  • If a static IP address is assigned to the equipment that will be connected to the switch port (e.g., Access Controller, video device, etc.), you will also want to provide that IP information

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