Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I am running RH Linux 7.2 and sendmail-8.11.6-3. I need to change the port that SMTP listens on. I changed it in my /etc/services file to 2525. I then changed my SMTP option in my sendmail.cf file to look like this:
O DaemonPortOptions=Port=2525, Name=MTA
When I restart everything I can see mail getting to my server but I get connection refused when it tries to send it. If I put things back on to port 25 SMTP then sends that mail.
example of /var/maillog showing connection refusal:
Jan 17 13:38:07 server1 sendmail: g0HIc7S01165: from=<email@example.com>, size=0, class=0, nrcpts=1, proto=SMTP, daemon=MTA, relay=server1 [10.3.2.200] (may be forged)
Jan 17 13:38:07 server1 sendmail: g0HIc7S01167: from=<firstname.lastname@example.org>, size=1364, class=0, nrcpts=1, msgid=<email@example.com>, proto=ESMTP, daemon=MTA, relay=server1 [10.3.2.200] (may be forged)
Jan 17 13:38:07 server1 sendmail: g0HIc7S01167: to=<firstname.lastname@example.org>, delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=31364, relay=mail.abcdigital.com. 220.127.116.11], dsn=4.0.0, stat=Deferred: Connection refused by mail.abcdigital.com.