ubuntu check what ports are in use code example

Example 1: ubuntu check process on port

sudo lsof -i:22

Example 2: check if port is running in ubuntu

# Any of the following
sudo lsof -i -P -n | grep LISTEN
sudo netstat -tulpn | grep LISTEN
sudo lsof -i:22 # Port
sudo nmap -sTU -O IP-address-Here