Pushing an Email Message in Mail Queue

This section provides an example using Sendmail a Mail User Agent (MUA) to transfer a remote email message, which is stored in the mail queue waiting for a connection to the remote machine.

On the Internet, not all machines are reachable all the time. Sendmail use a mail queue to manage emails for remote machine that not reachable. Here is an example session of using Sendmail as a MUA to transfer a remote email to a machine that is not reachable:

$su root

#rm /var/log/mail.log
#rm /var/spool/mail/herong
#rm /var/spool/mqueue/*
#sendmail -X /var/log/mail.log -v herong@hotmail.com
herong@hotmail.com... hotmail.com: Name server timeout
herong@hotmail.com... Transient parse error -- message queued 
                      for future delivery
From: root@darkstar.home.com
To: herong@hotmail.com
Subject: Second Test

Hi. This is another test.
.
herong@hotmail.com... queued
#

#more /var/log/mail.log
00088 <<< herong@hotmail.com... hotmail.com: Name server timeout
00088 <<< herong@hotmail.com... Transient parse error -- message queued 
                                for future delivery
00088 <<< From: root@darkstar.home.com
00088 <<< To: herong@hotmail.com
00088 <<< Subject: Second Test
00088 <<< 
00088 <<< Hi. This is another test.
00088 <<< .
00088 <<< herong@hotmail.com... queued

#ls /var/spool/mqueue
dfUAA00088   qfUAA00088
#more /var/spool/mqueue/dfUAA00088
Hi. This is another test.
#more /var/spool/mqueue/qfUAA00088
V2
T1216860066
K1216860066
N1
P30100
/I3/1/158
Mhost map: lookup (hotmail.com) deferred
Fb
$ root@localhost
$root
RPFD:herong@hotmail.com
H?P?Return-Path: <root>
HReceived: (from root@localhost)
      by darkstar.home.com (8.9.0/8.9.0) id UAA00088
      for herong; Thu, 23 Jul 1998 12:35:29
H?D?Date: Thu, 23 Jul 1998 12:35:29
H?x?Full-Name: System Admin
H?M?Message-Id: <199807230041.UAA00088@darkstar.home.com>
HFrom: root@darkstar.home.com
HTo: herong@hotmail.com
HSubject: Second Test
.

Notice that:

Table of Contents

 About This Book

 1957 - FORTRAN Language Developed by IBM

 1970 - UNIX Operating System Developed by AT&T Bell Labs

 1971 - FTP Protocol Created by Abhay Bhushan

 1972 - C Language Developed by Dennis Ritchie

 1976 - vi Text Editor Developed by Bill Joy

 1977 - Apple II Designed by Steve Jobs and Steve Wozniak

 1977 - The Bourne Shell Developed by Stephen Bourne

 1978 - The C Shell Developed by Bill Joy

 1978 - Bash (Bourne-Again Shell) Developed by Brian Fox

 1979 - The Tcsh (TENEX C Shell) Developed by Ken Greer

1983 - "Sendmail" Mail Transfer Agent Developed by Eric Allman

 What Is Sendmail?

 Using Sendmail as a Mail User Agent (MUA)

Pushing an Email Message in Mail Queue

 Using Sendmail as a STMP Server Daemon

 1984 - Macintosh Developed by Apple Inc.

 1984 - X Window System Developed a MIT Team

 1991 - WWW (World Wide Web) Developed by Tim Berners-Lee

 1991 - Gopher Protocol Created by a University of Minnesota Team

 1995 - Java Language Developed by Sun Microsystems

 1995 - PHP: Hypertext Preprocessor Created by Rasmus Lerdorf

 2002 - .NET Framework Developed by Microsoft

 References

 PDF Printing Version