Re: missing nullmailer feature in dma(8)/dmagent

On Tue, Oct 28, 2014 at 11:30:49AM +0100, Harald Schmalzbauer wrote:
>  Hello,
> 
> I haven't found a way to instruct dma(8) to also forward unqualified
> recipients to the relayhost. It always delivers unqualified addresses
> locally (if not translated by "aliases").
> 
> ssmtp(8) provides an option to define a recipient address for all local
> recipients who's ID is <1000.
> nullmailer(7) does exactly what I want, it doesn't care about the host
> part of the recipient address, it just passes it over.
> 
> I'm missing an option for dma(8), which disables local delivery
> completely, or like ssmtp, optionally only for ids <1000 resp. not
> existing local users.
> 
> Why?:
> Maintaining aliases at each machine is too expensive.
> My aim is that any operator or daemon of any (human-users-less) machine
> can simply drop mails to 'chief' or 'root' or 'monitor'. Then there are
> MSAs (I don't call them mailhub, in my world a mailhub stores email,
> which often is called a "mailhost"), and only these MSAs care about
> recipient aliasing and delivery to mailhub or relayhost. With that setup
> I have exactly one (resp. each redundant MSA) place to maintain aliases
> and/or other forwarding rules/mailertables etc. Since most smtp-agent
> implementations handle multiple A records – although I haven't found one
> which evaluates MX records – and I have more than one MSA, I can pretty
> reliably guaranteee that any failing machine/device/daemon can drop a
> note which won't get lost. If I did aliasing on the mailhub instead at
> the interposed MSA, I'd loose poor mans' redundancy…
> 
> According to dma(8) on 11-current, it's the same like in ports
> (mail/dma), which I used for testing.
> I like the decision to replace sendmail, since almost any time in the
> past when I really needed to use the fullfeatured MTA capabilities, I
> had to replace base sendmail with a SASL extended version…
> But I'd still need to spread nullmailer(7) with current's dma featrues
> in 11.
> 

The NULLCLIENT feature should exactly be what you are looking for, no?
As written in the manpage:

----
Bypass aliases and local delivery, and instead forward all mails to
the defined `SMARTHOST'.  `NULLCLIENT' requires `SMARTHOST' to be
set.
----

regards,
Bapt