Hide SSH entirely with port knocking

Hide SSH entirely with port knocking
Port 22 closed to the world, opens only for you. Looks like the box has no SSH at all:
— apt install knockd -y
— Define a secret sequence in /etc/knockd.conf: knock 7000, 8000, 9000 in order to open 22 for your IP
— The open command: ufw allow from %IP% to any port 22, with a matching close after 10s
— Set seq_timeout = 5 so a port scan can't stumble onto the sequence
— Open it from your laptop: knock yourserver 7000 8000 9000 then ssh in
Zero bots find a closed port. Try it tonight.