Ufw (Uncomplicated FireWall) is the firewall application that comes with a default installation of Linux Mint 17 – Cinnamon or MATE. This article shows how to replace it with FirewallD, a firewall application that has support for dynamic rules and network zones. It originated from the Fedora project.
FirewallD comes with a command-line utility called firewall-cmd, a graphical interface called firewall-config, and an applet called firewall-applet. These instructions are for installing the whole set on the Cinnamon edition. See this forum post for how to do the same on Linux Mint 17 MATE.
The whole process involves removing or uninstalling Ufw, then installing FirewallD and customizing the default configuration using firewall-config. To start, launch a shell terminal, then type the following command:
sudo apt-get remove ufw && sudo apt-get install firewall-applet.
The second part of that command will not only install the applet, but will also install the main application (FirewallD) and firewall-config. If you’d rather install them from the distribution’s graphical package manager, launch it, then search for “firewall-applet.” You should be able to install them from there.
As part of the installation, the applet is included automatically in the list of startup programs. If you look in the Startup programs module of the distribution’s System Settings, you should see it listed.
This screenshot shows the entries in the applet’s menu on the panel.
And this one shows firewall-config. The default network zone is Public, and out of the box, some programs, like ssh, are allowed in. If you installed the SSH server package (openssh-server), you might want to configure the firewall to allow connections to the SSH server only from the local network, or disable ssh from the Permanent and Runtime rules of the Public zone.