Install from source the latest experimental version of Postfix 3.2.
Go to http://www.postfix.org, and choose the "Download (source)" from the tab on the left. Choose a mirror, and find the source code download area for the latest experimental version of postfix:
Untar the file, and follow the instructions in "INSTALL" to compile and install the source code.
Test the server by using telnet localhost 25 to deliver mail to your local account.
Submit your journal on Blackboard by midnight on July 21.
2016-07-18: Please note that you may have an existing SMTP daemon already running, such as sendmail or exim; you will have to of course stop this daemon in order to run your new postfix daemon. (The easiest thing to do is probably just do an apt-get remove to get it out of your way.)
Also, if it is not clear how to test using telnet to do local delivery, a sample session would look like:
$ telnet localhost 25 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 220 langley.localdomain ESMTP Postfix helo langley.localdomain 250 langley.localdomain mail from:250 2.1.0 Ok rcpt to: 250 2.1.5 Ok data 354 End data with . Subject: test email This is a test . 250 2.0.0 Ok: queued as C09991825D1 quit 221 2.0.0 Bye Connection closed by foreign host. $ tail -20 /var/spool/mail/langley From langley@localdomain Mon Jul 18 11:19:08 2016 Return-Path: X-Original-To: langley@localdomain Delivered-To: langley@localdomain Received: from langley.localdomain (localhost [127.0.0.1]) by langley.localdomain (Postfix) with SMTP id C09991825D1 for ; Mon, 18 Jul 2016 11:18:31 -0400 (EDT) Subject: test email Message-Id: <20160718151851.C09991825D1@langley.localdomain> Date: Mon, 18 Jul 2016 11:18:31 -0400 (EDT) From: langley@localdomain This is a test $ date Mon Jul 18 11:19:25 EDT 2016