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OK so this is driving me crazy.
Running sendmail on CentOS. It's running, and listening on 25:
[root@mysqlslavebackup ~]# nmap -sS -O -sV 127.0.0.1 Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2013-03-21 10:46 PDD<br> Interesting ports on localhost.localdomain (127.0.0.1):<br> Not shown: 1665 closed ports<br> PORT STATE SERVICE VERSION<br> 22/tcp open ssh OpenSSH 4.3 (protocol 2.0)<br> 25/tcp open smtp Sendmail 8.13.8/8.13.8<br> 53/tcp open domain<br> 111/tcp open rpc<br> 631/tcp open ipp CUPS 1.2<br> 739/tcp open rpc<br> 953/tcp open rndc?<br> 3306/tcp open mysql MySQL 5.5.11-enterprise-commercial-advanced-log<br> 5901/tcp open vnc VNC (protocol 3.8)<br> 5902/tcp open vnc VNC (protocol 3.8)<br> 5903/tcp open vnc VNC (protocol 3.8)<br> 6001/tcp open X11 (access denied)<br> 6002/tcp open X11 (access denied)<br> 6003/tcp open X11 (access denied)<br>
I can telnet to 25 from the localhost, but from any other machine it appears the port is closed. iptables are off, and even if they were in I have an entry to open the port.
Can't for the life of me figure out what the heck it would be other than the fact this used to be a Zimbra mail server, but it has been uninstalled and there's no record of it in port bindings.
Any input would be awesome! Thanks!