test connection to a remote IP / port

nc -z <IP> <TCP port> OR nc -zu <IP> <UDP port>
-z: Specifies that nc should just scan for listening daemons, without sending any data to them -u: Use UDP instead of the default option of TCP.
Sample Output
# nc -zu 4670
Connection to 4670 port [udp/*] succeeded!

By: frank514
2011-04-01 04:08:53

What Others Think

The man page for nc states that UDP tests will always succeed and that -zu is useless.
DEinspanjer · 559 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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