[Nix-dev] NixOS Postfix service module config: why empty local_recipient_maps value?

[James Cook]

On 31 December 2014 at 14:11, aldiyen <aldiyen at gmail.com> wrote:
> Hello,
>
> I just started trying to use NixOS a little under a week ago, and after
> installing the Postfix service I found that I was having trouble preventing
> my server from sending backscatter. After some searches, I found that when
> the local_recipient_maps setting is empty (which it always is with the
> config that is created), Postfix will accept email for unknown local
> recipients and then send a delayed bounce notification. (See
> http://www.postfix.org/LOCAL_RECIPIENT_README.html)
>
> What is the reasoning behind the decision to set it up this way, without the
> option to override it? Is there some expected configuration or use case that
> I'm missing here?
>
> Thanks! Hopefully I'm following proper etiquette here -- I just joined the
> mailing list today
>
> -aldiyen

(+Michael Raskin, who git blames for that line of postfix.nix)

I don't use postfix, but if that's not configurable, it's probably
just because nobody bothered to add a configuration variable.  It
should be easy to add it (nixos/modules/services/mail/postfix.nix).

We probably shouldn't be overriding postfix's default by default,
unless there's some incompatability with NixOS ("The default setting
... assumes that you use the default Postfix local(8) delivery agent
for local delivery"), especially given the warning against setting it
to empty at the URL you sent.

James