xegr...@gmail.com wrote:
> Hi. In a new install of Postfix 3.4.7-0+deb10u1 on Debian buster, I
> would like Postfix to append $myhostname instead of $myorigin to
> local mail with a From header containing just a username, like cron
> or fail2ban emails. This server is listed in mx records for
> example.com.
I see you are using Gmail. One must be careful and look at the "Show
original message" in order to see what is actually being set on
headers as Gmail does not display that information to you otherwise.
For example if a comment is included then Gmail will display the
comment and hide the address.
Cron emails look like this for me:
From: CronDaemon <r...@anxiety.proulx.com>
To: r...@anxiety.proulx.com
In Gmail that would display the "CronDaemon" comment and the root@
address part would be hidden. One must use Show original message with
Gmail in order to see the actual contents of the header.
If you want a specific From: then either set $myorigin to the domain
you wish, or do not set myorigin and let it use $myhostname which is
the default.
http://www.postfix.org/postconf.5.html#myorigin
> In older Postfix installations (3.1) it seemed that only setting the
> below would be enough for local mail to be addressed from, for
> example, r...@mx.example.com. Wondering what I am missing or what
> to check next.
Are you thinking of "masquerade_exceptions = root" with
"masquerade_domains = example.com" here? That would match the
description as you have written.
> myhostname = mx.example.com
> myorigin = example.com
> mydestination = mx.example.com, localhost
The above will make usern...@example.com be the From: address for
locally created email. But the system will not accept mail for that
domain since it does not appear in mydestination. I think
mydestination should include $myhostname here.
Meanwhile, I always have localhost.$mydomain in my list too.
mydestination = $myhostname, localhost.$mydomain, localhost
> /etc/mailname is mx.example.com
Debian has a downstream patch that allows "myorigin = /etc/mailname"
and the actual contents in that file in order to facilitate a generic
image being customized across several different MTA installations all
uniformly the same way. The contents of /etc/mailname are only used
if also using the Debian patch functionality myorigin = /etc/mailname
AFAIK. In the above you are not setting it to /etc/mailname and
therefore that file's contents are not used.
> postconf -n output https://pastebin.com/WwVdT8CF
I see:
append_dot_mydomain = yes
Not sure if this plays into what you are asking. The default is yes.
But previously you might have had it set to no.
http://www.postfix.org/COMPATIBILITY_README.html
http://www.postfix.org/postconf.5.html#append_dot_mydomain
> If I remove $myorigin than all mail ends up going to @mx.example.com and
> bounces.
Why is it bouncing? And isn't mail going to @mx.example.com exactly
what you have asked for? Why does that mail bounce?
Bob
