is SMTP blocked or filtered?

  • Posted May 28, 2014

Set up postfix on a droplet but trying to connect remotely to port 25 there is no response, although the connection is not rejected or closed. There is no response via nc or telnet on that port. ufw is set up to allow it with a rule ACCEPT tcp – anywhere anywhere tcp dpt:smtp

And on the droplet, ‘nc localhost smtp’ works as expected.

Is DO filtering or blocking port 25 upstream?


Submit an answer
You can type!ref in this text area to quickly search our full set of tutorials, documentation & marketplace offerings and insert the link!

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

I am so, Please help me. I use, port 465. Now I cannot send emal from joomla 3.6.5. I send a ticket to Support Team but 3 days they donot answer for me.

Could it be your isp filtering port 25? Some set it so port 25 can only route to isp mail servers. <br>

Please file a support ticket so we can sort it out. Thanks!