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Is there a command to tell me what MTA/sendmail a unix system uses?

Thanks very much

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Are you actually on the mail server, or are you trying to figure it out remotely? – cjc Sep 21 '12 at 12:29
up vote 3 down vote accepted
[root@dev ~]# netstat -tlnp |grep :25
tcp        0      0      *                   LISTEN      1614/sendmail  


[root@dev ~]#  lsof -n -i :25
sendmail 1614 root    4u  IPv4 1413591375      0t0  TCP (LISTEN)

That should do the trick.

If you can't access the server, telnet to port 25 on it, most servers will tell you.

[bart@dev ~]$ telnet 25
Connected to
Escape character is '^]'.
220 ESMTP Postfix
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tried the first way and it just says "master" not "sendmail" – Alex Sep 21 '12 at 12:47
And what doe the other options tell you? – Bart De Vos Sep 21 '12 at 12:58
ah crap, I closed it now, i found out via google that 'master' is postfix – Alex Sep 21 '12 at 13:03
@Alex, if you look at the /proc filesystem, you can see the command line for "master". For example, if the PID of master is 2804, then cat /proc/2804/cmdline shows /usr/libexec/postfix/master. This saves the googling, and makes the identification with postfix unambiguous. – cjc Sep 21 '12 at 13:59

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