I have installed Debian 8 today, and so far so good. What I want to achieve now is to install firewall but can't find Firestarter in repos (discontinued ?). So, I have installed a GUFW and set it up.
After some time running GUFW, it spits out some errors and the Graphical Interface is closed. Because of that I'm afraid that my firewall might not work correctly. Is there any way I can test or check if my firewall is working correctly as it should?