lda / postfix / dovecot -- bounced messages not working

[Aki Tuomi]

On 30.03.2018 02:12, Scott Ruckh wrote:
> I saw another thread about this topic, but I did not understand the
> solution. . .
>
> I recently discovered my bounced messages were not getting delivered. 
> Obviously since I was not getting any messages, I thought everything
> was fine.
>
> Anyway, my maillog has entries similar to below for bounced messages:
>
> Mar 29 10:48:09 firewall postfix/pipe[9089]: 19565807:
> to=<myuser at my.domain>, relay=dovecot, delay=0.11,
> delays=0.02/0.01/0/0.08, dsn=5.3.0, status=bounced (command line usage
> error. Command output: lda: Fatal: Invalid -f parameter: Missing domain )
>
> In the previous thread discussing this issue it mentioned that this
> was a dovecot error and possibly due to a dovecot 2.3.0 upgrade.  I am
> running dovecot-2.3.0-1.1 on a CentOS 7 server.  The solution from the
> other thread simply stated that the original poster is instead using
> lmtp instead of lda, or at least that it was I got from the thread.
>
> If using lmtp instead of lda is the correct solution, could I get an
> example of what configuration changes need to be made to make that
> happen?
>
> Otherwise, has anyone else seen this error and know the solution to
> make it work.
>
> My current dovecot configuration for postfix (master.cf) is using the
> de-facto standard from many web docs:
>
> dovecot   unix  -       n       n       -       -       pipe
>    flags=DRhu user=vmail:vmail argv=/usr/libexec/dovecot/deliver -f
> ${sender} -d ${recipient}
>
> This is the same configuration that was originally setup and has
> worked for years; until the bounced message problem was recently
> discovered.
>
> If anyone has seen this error and knows the solution, I would
> appreciate the help.
>
> Thank You.
> Scott

This is because dovecot 2.3 expects ${sender} to contain domain name.
Using -f someone will break, but -f someone at somewhere will work.

Aki