Send mail telnet / test for open relay

determine the MX for the domain

set type=mx

should return something like:Server:
Address: preference = 10, mail exchanger = nameserver = internet address = internet address =

The last two lines are the mail server (MX = Mail Exchange). In this case, and

telnet 25

Server responds with: 220 SMTP

Server responds with: 250 OK

Server responds with: 250 Address Ok.

Server responds with: 250 OK

Server Responds (or may not): 354 Enter Mail
Enter message, then on a new line,


The message should now be sent. By modifying the MAIL FROM and RCPT TO lines, you can test for open relay.

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