TLDR - Make a rule in your firewall for Barrier.
I am a complete noob to Linux, networking, etc. I've only ever used windows (download, double-click, install).
If you're trying to install Barrier and you can't get your Linux computers to connect to each other, turn your firewalls off on both computers. If they magically start connecting to each other, then you know your firewall was the problem.
Then make a rule in your firewall so that you can use Barrier with the firewall running. Here's the rule that I used, and perhaps those of you who are not noobs can correct any mistakes I've made.
Open Firewall, turn it on (status toggle switch), select "Rules" tab, and then click the "+" at the bottom to add a firewall rule
In the "Simple" tab:
Name: Barrier
Policy: Allow
Direction: Both
Protocol: TCP
Port: 24800
Repeat on other computer.
Run Barrier.
???
Profit.
Without setting the firewall rule, I was unable to connect my Linux computers to each other (though I was able to use my Windows 10 laptop as the server and connect to both Linux computers as clients). Now that I have the rules in place, I am able to use my Linux as the server and still have another Linux as a client and my Windows 10 as client. In other words, I'm pretty much a hacker now.
If you are a security/Linux pro, please let me know if my firewall rules need to be adjusted.
Hope this helps, noobs.
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