Open Relay Testing
November 29, 2009
Want to test if your SMTP server is an open relay? Here's a couple of methods provided by abuse.net.
Telnet
If you have access to the mail server (for example, it's on your Virtual Private Server, run (as a normal user):
telnet relay-test.mail-abuse.org
This will run a series of tests on the mail server.
Web
You can run the same tests using a web interface at http://www.abuse.net/relay.html.
