Port Forwarding the Mac OS X Firewall


On 10.4 Tiger

  1. Open Transmission, go to Preferences >> Network and enter a number for the port. It is recommended you pick a random number between 49152 and 65535. Let's use 50001 for now. Then quit Transmission.
  2. Open System Prefs >> Sharing >> Firewall. Click "New." In the "Port Name" pop-up menu, select Other, and fill in the settings as follows:
  3. Click OK.
  4. NB: To disable the firewall, click Stop.

On 10.5 Leopard

Upon opening Transmission for the first time, a Mac OS X dialogue box should appear asking if you will allow Transmission to receive incoming connections. Click Accept.

If this doesn't happen, you can add Transmission to Leopard's firewall manually:

  1. Open System Prefs >> Security >> Firewall. Make sure "Set access for specific services and applications" is selected.
  2. Click the "+" button and select Transmission from you Applications folder.
  3. Make sure the pull down menu is set to "Allow incoming connections".