===== Overview =====
[[http://tmade.de|Home tmade.de]]

[[http://wiki.tmade.de|Home Wiki]]

==== telnet ====
Please follow the instruction to send a mail via telnet:

<code>
------
Mailserver testing
------
telnet localhost 25
.
.
.
helo testmail.org (Identify and demanding SMTP-Modus)
mail from:test@testmail.org (addressor/ sender)
rcpt to:test_receiver@linux.de (Receiver)
data (enables to write mailcontent)
.    (quit insert mode)
QUIT (close session)

Tip:
reset enable to send addtional emails
</code>

**Note:** There´s "helo" and "ehlo". Difference:

"helo" = Welcome to the server

"ehlo" = Enhanced HELO

==== mail ====

An email can be send from comandline with the progamm "mail". 

Example:

  MAILADDR=myemail@test.de
  echo "Test" | mail -s "Another Test" ${MAILADDR}
  echo "Test" | mail -s "Another Test for ${HOST} - `date`" ${MAILADDR} -a "FROM: mail@domain.org"                             #Include sender-adress - old syntax until ~ 2010
  echo "Test" | mail -s "Another Test for ${HOST} - `date`" ${MAILADDR} -r "mail@test.de"                                      #Include sender-adress "mail@test.de" for newer "mail" version
  echo "test" | mail -s "Test mail" -S "smtp=10.1.2.3" "to-adress@test.de" -r "from-adress@test.de"                            #Include mailrelay "10.1.2.3"
  

==== sendmail ====
Another way to send mails via commandline/ scripts:

First you have to create a file called "text" with example content:

<code>
To: username@domain.com
Subject: any-text
From: username@domain.com

Any mail content!
</code>
**Note:** There **must** be an empty line between "From:" and "Content"!!

Create a executable script (e.g. permission 755) to send the mail (also to run it with cronjobs for automatism):
<code>
#!/bin/bash

/bin/cat /scripts/text | /usr/sbin/sendmail -t
</code>

Another way:
<code>
#!/bin/bash

/bin/cat <<EOF | /usr/sbin/sendmail -t
To: username@domain.com
Subject: any-text
From: username@domain.com

Any mail content!
EOF

</code>

==== wall ====
To send a notification to local connected users:

  echo "SYSTEM BEING SHUT DOWN IN 5 MINUTES" | wall                                                                #Message to local connected users