Linux Mail Server Setup

Postfix SMTP Server Setup Howto for RHEL/CentOS 6

INSTALL POSTFIX AND DOVECOT 

 [root@ttc ~]# yum install -y postfix dovecot

Edit the file /etc/postfix/main.cf and uncommend the lines below.

inet_interfaces = all
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
home_mailbox = Maildir/

In mydestination make the comment in other two lines

If Your are using ipv4 set ipv4 like in ipv6 also for both set all

inet_protocols = ipv4

Make sure that all mail_spool_directory lines are commented out. 

Otherwise, it will override the setting in the home_mailbox line above. 

Start the Service

# chkconfig postfix on
       # service postfix restart
       # service postfix status
 

Add a user like nan

Type in the command newaliases in a terminal window. 

This will rebuild the aliases database file. 

# newaliases
 

In the Terminal window, type in the highlighted commands below

[root@ttc ~]# telnet localhost smtp
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 ttc.hpserver.com ESMTP Postfix
ehlo localhost
250-ttc.hpserver.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from:<nan>
250 2.1.0 Ok
rcpt to:<nan>
250 2.1.5 Ok
data
354 End data with <CR><LF>.<CR><LF>
Hi Nan  This is test mail 
Created on 22/12/2011
.
250 2.0.0 Ok: queued as DB7C213F6AC
quit
221 2.0.0 Bye
Connection closed by foreign host.
[root@ttc ~]# 
      

To check if the mail indeed exists

 [root@ttc ~]# cat /home/nan/Maildir/new/1324552225.V808I9f698M53702.ttc.hpserver.com

Return-Path: <nan@ttc.hpserver.com>
X-Original-To: nan
Delivered-To: nan@ttc.hpserver.com
Received: from localhost (localhost.localdomain [127.0.0.1])
    by ttc.hpserver.com (Postfix) with ESMTP id DB7C213F6AC
    for <nan>; Thu, 22 Dec 2011 16:39:18 +0530 (IST)
Message-Id: <20111222110948.DB7C213F6AC@ttc.hpserver.com>
Date: Thu, 22 Dec 2011 16:39:18 +0530 (IST)
From: nan@ttc.hpserver.com
To: undisclosed-recipients:;

Hi Nan  This is test mail
Created on 22/12/2011
[root@ttc ~]#

Dovecot POP3/IMAP Server Setup

Configure Dovecot

The settings for Dovecot are spread out across several files. Edit the files listed below and uncomment and updates its lines accordingly. 

/etc/dovecot/dovecot.conf

protocols = pop3 imap lmtp

/etc/dovecot/conf.d/10-mail.conf

mail_location = maildir:~/Maildir

/etc/dovecot/conf.d/20-pop3.conf

pop3_uidl_format = %08Xu%08Xv
pop3_client_workarounds = outlook-no-nuls oe-ns-eoh

Start the Dovecot service

[root@ttc ~]# service dovecot restart
Stopping Dovecot Imap:                                     [FAILED]
Starting Dovecot Imap:                                     [  OK  ]
[root@ttc ~]# chkconfig dovecot on
In the Terminal window, type in the highlighted commands below.

[root@ttc ~]# telnet localhost pop3
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
+OK Dovecot ready.
user nan
+OK
pass nan
+OK Logged in.
list
+OK 2 messages:
1 471
2 479
.
retr 1
+OK 471 octets
Return-Path: <nan@ttc.hpserver.com>
X-Original-To: nan
Delivered-To: nan@ttc.hpserver.com
Received: from localhost (localhost.localdomain [127.0.0.1])
    by ttc.hpserver.com (Postfix) with ESMTP id CF3D313F6AC
    for <nan>; Thu, 22 Dec 2011 16:12:14 +0530 (IST)
Message-Id: <20111222104228.CF3D313F6AC@ttc.hpserver.com>
Date: Thu, 22 Dec 2011 16:12:14 +0530 (IST)
From: nan@ttc.hpserver.com
To: undisclosed-recipients:;

HI This is test mail to you on 22/12/2011
.
retr 2
+OK 479 octets
Return-Path: <nan@ttc.hpserver.com>
X-Original-To: nan
Delivered-To: nan@ttc.hpserver.com
Received: from localhost (localhost.localdomain [127.0.0.1])
    by ttc.hpserver.com (Postfix) with ESMTP id DB7C213F6AC
    for <nan>; Thu, 22 Dec 2011 16:39:18 +0530 (IST)
Message-Id: <20111222110948.DB7C213F6AC@ttc.hpserver.com>
Date: Thu, 22 Dec 2011 16:39:18 +0530 (IST)
From: nan@ttc.hpserver.com
To: undisclosed-recipients:;

Hi Nan  This is test mail
Created on 22/12/2011
.
quit