Send an e-mail using command line

Here is a quick note how to send an e-mail using command line interface.

First Telnet to the mail server using port 25 and then run the following commands:

helo <SMTP_SERVER_DOMAIN> AUTH LOGIN <BASE64 USERNAME@DOMAIN> <BASE64 PASSWORD> mail from:<USER@DOMAIN> rcpt to: <USER@DOMAIN> data From: <USER@DOMAIN> Subject: test mail from command line this is test message number 1 sent from my router .

Don’t forget the “.” In the end

The authentication section is required for SMTP servers which prevent relay through the use of authentication. The username@domain and password should be typed in base64 which can be encoded using the following site:  http://www.base64encode.org/

And here is an example with Bezeq International SMTP server:

MRTR#telnet out.bezeqint.net 25          Translating "out.bezeqint.net"...domain server (192.115.106.35) Translating "out.bezeqint.net"...domain server (192.115.106.35) [OK] Trying out.bezeqint.net (192.115.187.185, 25)... Open 220 out7.bezeqint.net ESMTP Postfix at your service - please... helo bezeqint.net 250 out7.bezeqint.net AUTH LOGIN 334 VXNlcm5hbWU6 <BASE64 USERNAME@DOMAIN> 334 UGFzc3dvcmQ6 <BASE64 PASSWORD> 235 2.7.0 Authentication successful mail from:username1@bezeqint.net rcpt to:username2@domain.net data From:username1@bezeqint.net Subject: test mail from command line this is test message number 1 sent from my router . 250 2.1.0 Ok 250 2.1.5 Ok 354 End data with <CR><LF>.<CR><LF> 250 2.0.0 Ok: queued as 2229F5E2AF3

The following output is from Cisco IOS router.