It works now!
it turns out that cyrus-sasl-lib-2, cyrus-sasl WERE installed, but NOT
cyrus-sasl-plain. No idea why, or why it wouldn't generate some more
explicit warning somewhere...
But thanks Wietse! Installing it fixed the problem.
right now I am so toast that, since this is fixed, I must absolutely stop
until tomorrow but...
To Viktor: that how do I check what mechanism are being offered by the
receiving machine? I want to check that just for completeness
To the whole list: general comments on the postconf -n output that I posted
are still very welcome, to be sure there are no weak spots.
Thanks all, again!
Marco
2015-02-24 19:51 GMT+01:00 Viktor Dukhovni <postfix-us...@dukhovni.org>:
> On Tue, Feb 24, 2015 at 01:44:01PM -0500, Wietse Venema wrote:
>
> > Marco Fioretti:
> > > right, sorry. Here is the logs of a new message sent just now, with the
> > > configuration showed in my previous email:
> > >
> > > postfix/smtp[20851]: certificate verification failed for
> > > mx.example.com[xx.xx.xx.xx.]:587:
> > > self-signed certificate
> > > postfix/smtp[20851]: warning: SASL authentication failure: No worthy
> mechs
> > > found
> >
> > Could it be that the SENDING machine lacks the SASL
> > plugins needed for LOGIN and PLAIN? Try:
> >
> > # yum install cyrus-sasl{,-plain}
> >
> > (or its equivalent for non-RedHat platforms).
>
> Also, what mechanisms is the receiving machine offering?
>
> --
> Viktor.
>
