ID #1109

How to verify that my IP is open relay

1) You need to make sure that your mail relay has sign up for open IP relay and the IP is added to your mail relay account. To check if the IP is there, login to your DNS Exit account (or click on My Account if already login). You should see the mail relay account under "Mail Relay" section. Click either "Manage" or the mail relay name to enter Mail Relay Control Panel. You should see the IP there next to "Open Relay IP addresses".


2) Make sure you are at the IP address by visiting Make sure the IP you see at is the same as the IP you enter to your mail relay open IP.


3) You can test an email to verify that our mail relay system is open relay to your IP by using telnet command:


To verify that our mail relay system is open relay to your IP, you can use telnet command.

Note: Bold text are commands that you should type. Replace the red text with your own content. Blue text are comments.


>> telnet 25          #may use other ports  25, 26, 940, 80, 587 or 2525


Connected to (

Escape character is '^]'.

220 ESMTP Sendmail 8.14.4/8.14.4; Fri, 29 Apr 2016 20:41:55 -0400


250 Hello svn [], pleased to meet you

mail from:<>     # enter the from email

250 2.1.0 <>... Sender ok

rcpt to:<>    # enter the recipient's email

250 2.1.5 <>... Recipient ok

data            # type "data" and hit enter

354 Enter mail, end with "." on a line by itself

subject: test email        # type the subject

test email. ignore         # enter the email content

.                                    enter a period to indicate end the email

250 2.0.0 u3U0ftkg026733 Message accepted for delivery

quit                              # enter quit to end sending

221 2.0.0 closing connection

Connection closed by foreign host.


The email should get sent to destination. If the IP is not open relayed, after the rcpt to command, you should get the following error:

rcpt to:<>

550 5.7.1 <>... Relaying denied. Proper authentication

Tags: mail relay

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