Check if TCP port 25 is open

nc -zv localhost 25
Using netcat (nc) 25 can be replaced with the friendly value (smtp). Check error code for result or use -v option to echo output nc -z localhost smtp && echo open || echo closed nc -zv host protocol
Sample Output
Connection to localhost 25 port [tcp/smtp] succeeded!

By: toaster
2013-11-21 22:04:00

5 Alternatives + Submit Alt

What Others Think

You should use -v for echo status
Zulu · 454 weeks and 6 days ago
You're right ! Updated !
toaster · 454 weeks and 6 days ago
Works on Mavericks!!
karthik_g · 453 weeks and 2 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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