listen to UDP data on local port with netcat

Question

netcat -ul -p2115 fails with a usage statement. What am I doing wrong?

Thanks!

Answer 1

To quote the nc man page:

 -l      Used to specify that nc should listen for an incoming connection rather than initiate a connection to a remote host.  It is an error to use this
         option in conjunction with the -p, -s, or -z options.  Additionally, any timeouts specified with the -w option are ignored.

The key here is that -p cannot be combined with the -l flag. When using the -l flag, any ports specified in the positional arguments are used. So instead, you could use the following:

netcat -ul 2115

Enjoy!

Answer 2

-p might be wrong.. This will work on redhat based distros..

nc -u -l 2115