OpenSnitch is a free and open source application firewall for Linux. It is written in Python and released under GNU General Public License v3.0. Using OpenSnitch, you can manage multiple nodes, configure system firewall rules with GUI, outbound connections filtering, integration with SIEM, and options to block ads, trackers or malware domains.
How to Install OpenSnitch Firewall on Ubuntu
To install OpenSnitch on your Ubuntu system (Ubuntu 23.04 later), open the terminal application and run below OpenSnitch install command.
sudo apt install opensnitch
After the installation you can open it via the Show Apps application menu from the Ubuntu dock.
Check your system top bar to open the GUI.
Note: If the daemon doesn’t auto start, run it using below commands.
sudo systemctl enable opensnitch
sudo systemctl start opensnitch
And you can also uninstall it using below command.
sudo apt remove opensnitch
Install OpenSnitch via DEB:
Download the latest OpenSnitch in .deb package file from the above download link and save it on your Downloads folder. After that open the terminal application and run below install command.
sudo apt install ./Downloads/python3-opensnitch-ui*.deb
Note: Here “python3-opensnitch-ui_1.6.4-1_all.deb” is the downloaded file. You can change above command based on your file name.