Barrier - screen control across physical devices

apt install barrier (on main and client)

or snap install barrier

SERVER

on Main computer (controller)
Barrier > Settings (check on Enable SSL, Require client cert, can leave port 24800)

create SSL

cd /home/USER/.local/share/barrier/SSL
mkdir -p Fingerprints
openssl req -x509 -nodes -days 1265 -subj /CN=barrier -newkey rsa:4096 -keyout Barrier.pem -out Barrier.pem
openssl x509 -fingerprint -sha1 -noout -in Barrier.pem > Fingerprints/Local.txt
sed -e "s/.*=//" -i Fingerprints/Local.txt

start Barrier

CLIENT
Barrier > Settings (check on Enable SSL, Require client cert, run same SSL commands as above

check on checkbox for Client, enter the Server IP from above into Server IP field

start service