How to test Postfix SMTP using Telnet

1. Telnet to postfix mail server using TCP port 25.
Command is telnet (servername/serverip) 25
response should be as follows

    220 ********************************************

2. Turn on local echo on your telnet client so that you can see what you are typing.
On Win 9x and NT 3.5/4.0 Telnet client this done by selecting the “preferences” from the “terminal” pull down menu, and checking the local echo radio button.  For Windows 2000 telnet client, issue command “set local_echo”, from the telnet command prompt.

3. Issue the following smtp command sequence

ehlo (your domain name)(enter)

response should be as follows

    250-servername
    250-PIPELINING
    250-SIZE 10240000
    250-VRFY
    250-ETRN
    250-ENHANCEDSTATUSCODES
    250-8BITMIME
    250 DSN

mail from: (your Email Address)(enter)
response should be as follows

    250 2.1.0 Ok

rcpt to: (recipient address)(enter)
response should be as follows

    250 2.1.5 Ok

data(enter)
response should be as follows

    354 End data with (CR)(LF).(CR)(LF)

To: (recipient’s display name)(enter)
Subject: (Subject field of Email message)(enter)
(Enter you body text)(enter)
(enter)
(enter)
response should be as follows

    250 2.0.0 Ok: queued as queueid

quit(enter)
response should be as follows

    221 2.0.0 Bye
    Connection closed by foreign host.

I hope this save’s someone time.