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I have written a Qt application that listens for UDP broadcast packets on the network interface p2p1. I have installed the application in Fedora 17 i386 in a VirtualBox VM. For some reason, the application is not receiving any broadcast packets that I am sending.

I installed and ran Wireshark and verified that the broadcast packets are indeed arriving on p2p1:

image description

Does anyone have any idea why the application (which is listening for UDP packets on port 41720) isn't receiving any of the packets? Some security setting or something?

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up vote 2 down vote accepted

The following set of steps were able to resolve the problem:

  1. Open a terminal and type:
  2. Enter your password if prompted.
  3. Click "Other Ports" on the left-hand side:
  4. Click the "Add" button on the right-hand side:
  5. Check "User Defined" and enter the values below:
  6. Click "OK" and then click the "Apply" button in the toolbar:
  7. If you are warned that selecting "Yes" will override any existing firewall configuration, you may safely click "Yes".

Note: the above instructions were copied from this page, which I am the author of.

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