The Mac inbuilt firewall is disabled by default. Why worry, and why should you enable it? The firewall is used to control connection to your Mac and from your Mac. Since Mac OS version 10.5.1 the firewall allows connection per application basis and not by port. This is useful as it allows users to easily configure the firewall settings without complex port settings and configurations.
In this tutorial, I will show you how to enable the Mac firewall and how to allow or block an application with the firewall incoming connection options.
How to enable the Mac firewall?
Open the Mac firewall settings in the Security and Privacy settings. Open the Mac menu in the top left corner, (). Go to the System Preferences and open the Security and Privacy settings.
In the Privacy and Security menu, open the Firewall tab and “Click the lock to make changes”. Enter the administrator username and password to unlock the Firewall settings and enable the Mac firewall.
Click the “Turn on Firewall” button to enable the Mac firewall.
If you want to allow or block application with the Mac firewall, open the Firewall Options.
Configure the Mac firewall
In the firewall options, you see several options to configure. If you want to disable all incoming connections to your Mac, you might want to enable the “Block all incoming connections” checkbox. However, this is not recommended as it will prevent applications that are installed on your Mac from incoming connect, including the network connections. If you block all incoming connections on your Mac, some applications may no longer function properly.
If you want to block an incoming connection for a specific application, search for it in the applications list. If you can’t find it, you can add the application with the (+) button and search for it. Change the Allow incoming connections settings to Block incoming connections.
The Mac firewall only offers the ability to block incoming connection, not for outgoing connections.
I hope this tutorial has helped you configuring the Mac firewall! Leave a comment or additional information in the comment field, thanks!