We want to achieve following with nginx smtp, please let me know if that's possible and can you help me with that ?
1) Our software will connect to NGinx on port 25 and will authenticate with the NGinx in the same manner as it would to SMTP Server. 3) NGinx should then authenticate against an internal UserID and Password and not our Internal SMTP Server. 4) If authenticated it should either accept the email from the software, or it should pass through the connection to the internal mail server with authentication that is on our internal mail server so the emails will be captured in the mailbox created for the software to allow for email tracking.
I am more concerned about 3rd step, is there some authentication that i can use to verify request within nginx before it can forward it to internal mail server?