Subject: Mail submission -- significant change of behaviour!
To: None <>
From: Havard Eidnes <>
List: tech-userlevel
Date: 11/04/2003 11:06:16

it used to be true that a NetBSD system with no mail system configured
to run in daemon mode and otherwise mostly left untouched from the
initial installation, (i.e. /etc/mailer.conf points to sendmail) but
connected to the Internet (i.e. working DNS & connectivity) could send
outgoing e-mail messages to other systems "out of the box".

With the one of the updates of sendmail to NetBSD-current over the
last year this is no longer possible.

Apparently sendmail has been split in two pieces, and one of them is
responsible for mail submission (smmsp).  Smmsp, however, appears to
be dependent on a running mail daemon on the local system.  If no such
daemon can be connected to on port 25, smmsp has it's own private mail
queue where the contents is *not* shown by mailwrapper's "mailq"
command.  Also, outbound e-mail is silently queued in smmsp's private
mail queue, so the user who submitted an e-mail may falsely live under
the impression that everything is as it should be.

To get outgoing e-mail going, you need to enable both sendmail and
smmsp (or start running postfix, which I don't think has a mode to
handle "just outgoing e-mail").  I'll admit that it's a long time
since I configured sendmail last, and I could not find an easy
configuration change to make it listen only to, so now some
of my systems have an exposed listener on port 25 where I did not have
one before and where I didn't really want one.  Tweaking the .mc file
for the sendmail configuration to make it listen only to
does not qualify as "an easy configuratin change".

Another alternative which has been mentioned to me is the package
mini_sendmail.  However, this solution appears to have two problems:
it is not part of the base system, and also appears to be dependent on
at least local configuration, if not also a host-local SMTP server.

A third alternative which has been mentioned is to make the sendmail
wrapper program u+s root.  This is not really viable as a local
override, since one will have to remember to do this every time user-
land is updated.  Also, I can imagine that this change would defeat
the whole security benefit of the sendmail / smmsp split, which would
also be bad, so is not a good alternative for the system as a whole.

Am I the only one who finds the implicit removal of the "outbound
e-mail works out of the box" feature Highly Annoying?


- Håvard