Released Postfix 3.1.0 With few fixs

Postfix is free, open-source, fast and popular, SMTP mail transfer agent (MTA) which is using widely as alternative for Sendmail. Postfix implements a high-performance parallelized mail-delivery engine. Postfix is often combined with mailing-list software (such as Mailman). Postfix can run on UNIX-like systems including AIX, BSD, HP-UX, Linux, MacOS X, Solaris, and more. The latest version of Postfix 3.1.0 released on February 24, 2016 with fix of TLS failure, causing the affected messages to accumulate in the deferred queue.

Add hostname entry into /etc/hosts file, so that it will discover the hostname when you are testing the postfix
configuration.

$ sudo nano /etc/hosts
192.168.0.100 mint.2daygeek.com

1) Install Postfix

All the modern Linux distribution by default having postfix binary package on their own repository, so we can easily install by issuing below single command. By default Sendmail installed most distribution so remove it before processing postfix installation.

[Remove sendmail, if its not installed you can skip]
$ sudo purge sendmail

[Install Postfix]
$ sudo apt-get install postfix 

Read the postfix configuration information, just hit ok.

Choose Internet site and hit ok.

Add your mail host name, then hit ok.

2) Configure Postfix

Edit the /etc/postfix/main.cf file and add below entry, reset of the things are configured properly while installing postfix.

$ sudo nano /etc/postfix/main.cf
home_mailbox = Maildir/

You can cross check & re-configure the configuration by running below command.

$ sudo dpkg-reconfigure postfix

3) Restart Postfix

Once you have done appropriate above changes, just fire the below commands to restart postfix service to take effect the changes on new configuration.

[For SysVinit Systems]
$ sudo service postfix restart
$ sudo chkconfig postfix on

[For systemd Systems]
$ sudo systemctl restart postfix
$ sudo systemctl enable postfix

4) Test Postfix

Now you are ready to test your postfix mail service whether its working fine or not, use the below tricks.

$ telnet localhost smtp
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 mint.2daygeek.com ESMTP Postfix (Ubuntu)
ehlo localhost
250-mint.2daygeek.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
quit
221 2.0.0 Bye
Connection closed by foreign host.

5) Test Postfix with User

Create user with /sbin/nologin shell to restrict login access.

$ sudo useradd -m magi -s /sbin/nologin
$ sudo passwd magi
$ telnet localhost smtp
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 mint.2daygeek.com ESMTP Postfix (Ubuntu)
ehlo localhost
250-mint.2daygeek.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
mail from: [email protected]
250 2.1.0 Ok
rcpt to: [email protected]
250 2.1.5 Ok
data
354 End data with .
Postfix mail server testing on LinuxMint 17.3
.
250 2.0.0 Ok: queued as 1C86CC351F
quit
221 2.0.0 Bye
Connection closed by foreign host.

See the below output.

# cat /home/magi/Maildir/new/1456376003.V801I1422d3M520795.mint.2daygeek.com
Return-Path: 
X-Original-To: [email protected]
Delivered-To: [email protected]
Received: from localhost (localhost [127.0.0.1])
    by mint.2daygeek.com (Postfix) with ESMTP id 1C86CC351F
    for ; Thu, 25 Feb 2016 10:22:46 +0530 (IST)
Message-Id: <[email protected]>
Date: Thu, 25 Feb 2016 10:22:46 +0530 (IST)
From: [email protected]

Postfix mail server testing on LinuxMint 17.3

Enjoy…)