OpenSnitch is a rare tool in the Linux ecosystem. It is a service with a friendly graphical desktop application which assists the user in blocking network connections based on which daemon or application is making the connection attempt. Most Linux firewall tools focus on blocking access to specific network ports or remote servers. OpenSnitch focuses on which program is trying to access the network or send network traffic to remote machines. The OpenSnitch service can monitor connection attempts, let us know which processes are trying to talk over the network, and to which remote servers. It’s an interesting and powerful tool, one which I felt deserved more attention.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word “Linux” in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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I personally use firewalld for just the GUI. I heard good things about OpenSnitch but never tried it. From just the pictures in the linked article, I would say OSnitch is more for beginners and overall easier to configure.
Just tried it out and it looks really promising
I was a huge user of LittleSnitch on Mac back in the days so this makes me very happy