CentOS Linux Server Guide

CentOS Mail Server

Test your Postfix SMTP Connection

 

First of all make sure that CentOS Linux Postfix Mail service is started

 
service postfix status
master (pid 4073) is running...

 

Then we check if the port 25 (default smtp port) is ready and listening
netstat -an | grep 25
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN

 

You might also want to ensure that Postfix service auto started at Level 3,4 and 5
chkconfig --list postfix
postfix 0:off 1:off 2:on 3:on 4:on 5:on 6:off

 

Else, you can start the postfix in the following
service postfix start
Starting postfix: [ OK ]

 

The following command tells the system to auto startup the posfix system and level 3,4 and 5
[root@mail ~]# chkconfig postfix on

 

Now, lets check the Postfix SMTP connection. The example below, we telnet to localhost (127.0.0.1) port 25 (smtp), then we using user account Jane to sent an email to James.
telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 mail.1a-centosserver.com ESMTP Postfix
ehlo mail
250-mail.1a-centosserver.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from:<jane>
250 2.1.0 Ok
rcpt to:<james>
250 2.1.5 Ok
data
354 End data with <CR><LF>.<CR><LF>
This is a test mail send from Jane
.
250 2.0.0 Ok: queued as 8E93F27DF3
quit
221 2.0.0 Bye
Connection closed by foreign host.
 

 

Where does our email go? All the new email send will be delivered to /home/user/Maildir/new. In our example below 1259937815.Vfd00Idf04dM230839.mail.1a-centosserver.com  is the new email, you can read the mail content using "cat" command.

 

 cd /home/james/Maildir/new
-rw------- 1 james james 475 Dec 4 09:43
1259937815.Vfd00Idf04dM230839.mail.1a-centosserver.com
[root@mail new]# cat 1259937815.Vfd00Idf04dM230839.mail.1a-centosserver.com
Return-Path: <jane@1a-centosserver.com>
X-Original-To: james
Delivered-To: james@1a-centosserver.com
Received: from mail (srv1.example.local [127.0.0.1])
by mail.1a-centosserver.com (Postfix) with ESMTP id 8E93F27DF3
for <james>; Fri, 4 Dec 2009 09:42:54 -0500 (EST)
Message-Id: <20091204144313.8E93F27DF3@mail.1a-centosserver.com>
Date: Fri, 4 Dec 2009 09:42:54 -0500 (EST)
From: jane@1a-centosserver.com
To: undisclosed-recipients:;

This is a test mail send from Jane

 

 

Back to CentOS Mail Server



Copyright 2011 http://www.1a-centosserver.com All Rights Reserved

All trademarks are the property of their respective owners.

Contact Us | Terms of Use | Privacy Policy