Quick Netcat commands

Check if a port is open

nc -z host.example.com 20-30 Example of output: Connection to 172.16.134.131 port 3389 [tcp/ms-wbt-server] succeeded!

File transfer with nc

Start by using nc to listen on a specific port, with output captured into a file:

       $ nc -l 1234 > filename.out

 Using a second machine, connect to the listening nc process, feeding it
 the file which is to be transferred:

       $ nc host.example.com 1234 < filename.in

 After the file has been transferred, the connection will close
 automatically.