An SMTP interoperability machine has been setup for testing with the open source version of sendmail 8.14. Do not use this machine to monitor your SMTP connectivity. It is for SMTP interoperability testing only! If you have any questions, you may contact postmaster@test.smtp.org. Feedback is always welcome.

The machine test.smtp.org is configured to support:

Mail sent to bouncer@test.smtp.org will return one message to the envelope sender of your mail and one to header sender of your mail. You can use this to see the results of your test and diagnose problems. NOTE: This service is currently disabled due to abuse. If you need use of this service, contact me as described above.

Mail sent to bit-bucket@test.smtp.org will be accepted and discarded. Use this e-mail address for testing.

If you wish to test SMTP authentication, 20 accounts have been created for testers to use. These accounts are of the form user01, user02, ..., user19, and user20. Likewise, they have passwords pass01, pass02, ..., pass19, and pass20 respectively. The realm (used by DIGEST-MD5) is set to test.smtp.org. Check recent activity in the MTA log (see below) to make sure nobody is using the number you are about to test with so you can distinguish your results from others in the log.

STARTTLS is using OpenSSL generated RSA certificates signed by the test.smtp.org certificate authority.

The MTA log are also available live for public viewing at: http://test.smtp.org/log

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