On Thu, Aug 09, 2012 at 06:50:26PM -0400, Deeztek.com Support wrote:
> >Operationally a multi-instance system is easier to support. It
> >takes a small bit of effort to build, this is well worth it.
>
> Maybe it's the way my brain works but what you are suggesting seems
> more complicated to me.
Modular systems have more pieces that complex monoliths, but the
pieces are simpler, and well chosen boundaries make it easier
to understand and manage the whole.
The multi-instance tutorial:
http://www.postfix.org/MULTI_INSTANCE_README.html#quick
walks you through setting up a two-stage MTA with a pre-filter
input and a post-filter output instance. Read the rest of the
tutorial for a more in-depth explanation.
It can be hard work to make simple things.
> Every example I've
> seen on the Internet on how to set up multiple instances does not
> take into consideration my configuration which a relay server with
> absolutely no authentication and no user accounts.
The example in the tutorial is also a relay system, and in case
that is just a feature of the output stage of the system, the
input stage is generic.
Most "examples" on the Internet are not worth reading, start with
the MULTI_INSTANCE_README file.
> I wouldn't be opposed in setting up the multiple instances as long
> as I can get some help setting it up but I'm going to need specific
> instructions and information. If this is something you are willing
> to do, I would be more than happy to do it.
I think that developing the postmulti tool, writing the tutorial
and explaining why you want to read it and use this approach is a
decent amount of help.
Just draw a diagram:
Input => Filter => Output
and configure the Input and Output stages as separate Postfix
instances. All mail entering the Input stage flows into Output
stage via the Filter.
The input stage handles access control and pre-filter queue
management. It has no interesting routing, just send everything
to the filter.
The Output stage does no access control (the input took care of
that), but it handles final signing and routing.
--
Viktor.
