Barrier is a software KVM application that allows sharing a keyboard and mouse connected to a server with one or more clients.

Generate server certificate

If you see "ERROR: ssl certificate doesn't exist" in the server logs, it's likely that Barrier has failed to generate a certificate. To correct this, generate one:

mkdir -p "~/Library/Application Support/Barrier/SSL/Fingerprints"
cd "~/Library/Application Support/Barrier/SSL"
openssl req -x509 -nodes -days 365 -subj /CN=Barrier -newkey rsa:4096 -keyout Barrier.pem -out Barrier.pem

When next started the server should write a new "Local.txt" file containing the key's fingerprint.

Issues with macOS Zoom

I use the macOS Zoom accessibility feature when sharing my screen via a capture card to hone in on specific application windows. Barrier seems to get confused about the cursor location when I'm using this: remember to Stop the Barrier server before zooming.