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I am running Fedora Core 5 with Postfix and Dovecot for email running.
When logged into the linux box, I can telnet localhost to both port 25 and port 110, and get a response. I have successfully manually entered an email message and then logged into the POP3 server and saw that message there.
However, when I try to set an account up on a different machine on the network, it can't connect to either the POP3 or SMTP services. Also, I'm having problems telnetting to the box on ports 25 and 110.
When I telnet to port 110 on that box, from another computer, I see that Dovecot is running, but then it becomes unresponsive. Telnetting to port 25 from another computer results in a disconnection.
I have verified that the daemons are running, and that the Linux firewall is configured to allow incoming connections on those ports. A netstat -l shows that the box is listening to ports 25 and 110 for connections on all interfaces.
OK, well I don't have access to that box from work (the box is at home) so when I get home I'll look at the log files and see what's going on.
The thing that confuses me about is that if I SSH to the box from my laptop, and then run 'telnet localhost 25' or 'telnet localhost 110' it works as it should. But if I just try to 'telnet 192.168.0.220 25' or 'telnet 192.168.0.220 110' from my laptop I have problems.
When telnetting to the POP3 directly (not through SSH first), Dovecot reports ready and that's it. It stops responding after that. I have to force my telnet app to disconnect.
When telnetting to the SMTP directly (not through SSH first), the screen will clear and telnet will close suddenly. There is no message or anything. It just closes.
I looked in /var/log/mail and didn't see anything obvious last night.
I have set the Linux firewall to accept connections on ports 25 and 110, and have applied the config changes, even restarted the box, but it's still not working. The fact that it's doing anything on those ports at all suggests that it's getting through the firewall, but after that it's running into some kind of problem.