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Port Mapping

You will want to use Port Mapping (aka Forwarding) if:

  • you are running a web, email or any other server on a client machine
  • you are running an application such as Timbuktu, ICQ or any other application which needs incoming connections on a client machine

There is no GUI interface to setup Port Mapping within IPNetShareX. Instead, you will have to work through a Terminal window of Mac OS X and manually configure Port Mapping with the "natd" command.

(note: <ENTER> represents clicking the Enter key on your keyboard)

To do this:

1. Make sure IPNetShareX is running.

2. Launch the Mac OS X Terminal application (this application resides in your Applications/Utilities directory).

3. Type:

ifconfig -a <ENTER>

This will give you a list of configured interfaces on your machine. Identify the interface which has the public IP address assigned to it. This is normally "en0" for configurations sharing a cable/DSL connection on the built in ethernet port. Interface names are identified by the first few characters of each entry, e.g.:

inet netmask 0xffffff00 broadcast

4. Enter the following command (change as needed):

sudo natd -n en0 -redirect_port tcp 80 <ENTER>


en0 is the interface name (change as needed).

tcp is the protocol (can be tcp or udp) is the client machine IP address (change as needed)

80 is the port (change as needed for your application)

The above command would forward all HTTP connection requests to a web server running on a client machine running on IP address

5. You will be prompted to enter your Administrator password. Do so, and click Enter again. You should return to the prompt. Your port mapping entry has been successfully implemented.

6. Repeat as needed.

For more information and other options regarding the "natd" command, enter:

man natd <ENTER>

Clicking the space bar advances the manual by one page.

Need More Help?

IPNetShareX is free for personal, educational, or non-profit use but does not include one-on-one technical support. You are welcome to join our NetTalk discussion list and post your support questions there. You may receive Priority Support for IPNetShareX by purchasing a Continued Care subscription on our web site or upgrading to IPNetShareX Pro.

IPNetShareX Pro users are encouraged to use our support center at