Complete TCP Handshake on a given host-port

nc -zvw 1 host port
Try to perform a fully TCP 3 way handshake on for a given host-port with a timeout of 1s.
Sample Output
$ nc -zvw 1 localhost 8000
nc: connect to localhost port 8000 (tcp) failed: Connection refused
$ nc -zvw 1 localhost 22
Connection to localhost 22 port [tcp/ssh] succeeded!

6
2012-07-13 20:02:17

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