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I'm running FC4 with SElinux and firewall turned off. I'm behind a hardware firewall that passes ports FTP,SMTP, SSH, POP, IMAP. However, I can't receive incoming email. I'm using postfix
1. grc.com shields up says all the port listed above are open except 25 (SMTP).
2. I can telnet localhost 25 and it works.
3. I can email to myself from myself and it works correctly.
4. I can't telnet port 25 from another machine in the same subnet plugged into the same Linksys router/switch
5. I can from another machine on the same subnet login via squirrelmail to read the self-to-self email test.
6. I can email from my system to another address outside without a problem. Just don't get any replies.
Is the mail daemon listening on the proper network address? Most distros now ship with a mail daemon that listens on localhost (127.0.0.1) so it can send and receive mail to itself as well as send outgoing mail to remote systems. However it won't be able to receive incoming mail from remote systems. Check 'netstat -pantu' and see what IP the daemon is listening on. If it's the wrong one, you likely just need to edit your mail config file.
Yup. That's the mail daemon and it's listening on localhost. "Master" is just the postfix master process. Because it's only listening on localhost it can only receive local mail. The postfix config should be in /etc/postfix/main.cf. Scroll down the config to the section on "RECEIVING MAIL" and see if the inet_interface directive is set to localhost (you'll see several different entries but only one will be uncommented). If it's set to localhost, then simply comment out that line with the '#' and then uncomment the line that reads "#inet_interfaces = all".
Okay, I moved back to sendmail, where I have more control over the configuarion. I now have port 25 listening everywhere and I get inbound email that I wasn't getting prior to this.
However, I'm now getting relay refusal messages from earthlink. They told me at tech support to use a authenticated smtp server and setup the SMARTHOST define in sendmail.mc. Only problem with that is it require a username and password. Usually, that's my full earthlink email address and password. I don't have any examples or doc to tell me the syntax of SMARTHOST other than the name of the ISP's server.