check listening port ubuntu code example
Example 1: ubuntu listening ports
# To see ports in use
sudo lsof -i -P -n | grep LISTEN
sudo netstat -tulpn | grep LISTEN
Example 2: see what is using a port ubuntu
$ sudo lsof -i:22
# To see ports in use
sudo lsof -i -P -n | grep LISTEN
sudo netstat -tulpn | grep LISTEN
$ sudo lsof -i:22