check all running ports ubuntu
sudo lsof -i -P -n | grep LISTEN sudo netstat -tulpn | grep LISTEN sudo ss -tulpn | grep LISTEN sudo lsof -i:22 ## see a specific port such as 22 ## sudo nmap -sTU -O IP-address-Here # Source https://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/