To protect your computer against unauthorized access by people on the Internet or your network,you can set up a firewall in your ubuntu. Firewalls block connections to your computer from unknown sources, which helps to prevent security breaches. If you use a router to connect to the Internet, the router may already have a firewall configured which regulates connections from the Internet to your network.
following post briefs the set up procedure of firewalls in ubuntu.
Most users will prefer to use Gufw, which is a graphical user interface program to configure UFW(uncomplicated firewall).
Click the below link to install and enable Gufw:
then the below shown dialogue box appears.
click on launch application and agree to install the package.
Now, to start Gufw, choose → →
To enable the firewall, simply check the box next to under “Actual Status”.
The default configuration is to deny connections. This means that a program attempting to connect to your computer will be denied. Certain programs or services which use the internet may require you to add an exception.
To add an exception:
- Click .
- You can choose from options for common programs and services, or you can manually add port exceptions in the or tabs.
- To find out what type of exception a particular program requires, you should consult the help for that program.