Can't Open Port 25

Posted April 1, 2014 8.8k views
I've been trying to open port 25 for postfix, and I can't figure out what I'm doing wrong. I can't telnet to the server with port 25, while I can telnet to other, like TeamSpeak3s port (30033). This is what my iptables looks like. # Generated by iptables-save v1.4.7 on Tue Apr 1 15:24:14 2014 *filter :INPUT ACCEPT [1326:1570360] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [841:176823] -A INPUT -p tcp -m tcp --dport 25 -j ACCEPT COMMIT # Completed on Tue Apr 1 15:24:14 2014

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4 answers
Is there anything running on port 25?
sudo netstat -plutn | grep 25
sudo netstat -plutn | grep 25
tcp 0 0* LISTEN 28291/master
tcp 0 0 ::1:25 :::* LISTEN 28291/master
I am trying to open the port for posfix, but the server can't receive any emails. After a while I get this response on gmail, trying to send an email:

Technical details of temporary failure:
The recipient server did not accept our requests to connect. Learn more at
[(0) []:25: Connection refused]
Postfix is listening on the loopback interface. You have to configure it to listen on See
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