Questions about: firewall

Hola! I recently upgraded from Mint 7 to Mint 9 and when I went through all the programs that shipped with this release I found gufw, the firewall application. Maybe it was there in Helena as well, but this is the first time I've noticed it. However,
It sounds like the question is about a host-based firewall on an Ubuntu PC. IF the machine never leaves the NAT-based network (ie, it is not a laptop that you take to coffee shops and use on free wifi networks), AND there are no ports open on your ro
To list open ports use the netstat command. For example: $ sudo netstat -tulpn | grep LISTEN tcp 0 0 127. 0