I would probably try from the command line to see if you can get more information. Sounds like you think that it's from a MUA vs 3rd party probes that only want to know what ports are open vs completing the handshake. 2000 every day does seem excessive for this type of port knocking.Why it is terminating early could be anything from protocol/ciphers to certificate errors. The above line should allow you to see more detail.
I think one of the test certificate sites will alert you to these client/server cipher problems... https://www.ssllabs.com/ssltest/
HTH,
Jim
Code:
% openssl s_client -connect your.mail.server:587 -starttls smtp -debugI think one of the test certificate sites will alert you to these client/server cipher problems... https://www.ssllabs.com/ssltest/
HTH,
Jim
Statistics: Posted by JDunphy — Tue Jan 07, 2025 1:56 am