Hello OpenSuSE Lister's -  I think I have encountered a change on BSD Sendmail's behavior (version 8.15.2-150000.8.9.1) that coincides with upgrading OpenSuSE 15.4. I want to run sendmail on some systems that are running another MTA also (such as Apache James, Axigen) For many many moons of OpenSuSE releases, I accomplish this feat by turning off the running of sendmail in daemon mode. That is accomplished by NOT including the -bd parameter for sendmail when starting the systemd sendmail service. This effectively turns off the ability for sendmail to listen for incoming connection request on port 25. But this configuration did not stop sendmail from sending emails for clients such as clamd, cron, etc., which use sendmail internally to send emails as needed. And it did not cause a conflict of the usage of port 25 between sendmail and another MTA.

As of OpenSuSE15.4 the ability of sendmail to send emails, and not receive them is broken. Trying to send an email (via localhost) - such as the following test -

echo "Subject: sendmail test from Quasar" | sendmail -v marc@marcchamberlin.com

results in the following useless and misleading error message -

marc@marcchamberlin.com... Connecting to [127.0.0.1] port 25 via relay...
marc@marcchamberlin.com... Deferred: Connection refused by [127.0.0.1]

I tried exploring firewalld, routes, dhcpd and other network tools all to no joy. The one thing I have found, that will work and get sendmail to send email messages, is to restore the -bd parameter, which up to 15.4 has never affected sendmail's ability to send emails. But as I already said, I cannot use -bd for systems on which I am running another smtp mail server also.

If others are willing to concur that this is a new bug, I will happily submit a bug report. I also need to know where to submit it, I tried using Google and got lots of hits on places where sendmail bug reports had been made. Should I submit a bug report on OpenSuSE's bugzilla and let the maintainers figure out where to forward the bug report?

Alternatively, perhaps some kind guru knows of an alternative way to configure BSD Sendmail to send but not receive emails?

As always, thoughts and comments are much appreciated!   Marc....

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<b>Computers: the final frontier. These are the voyages of the user Marc.<br> 
His mission: to explore strange new hardware. To seek out new software and new applications.<br> 
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