Postfix as a relay hub

HI there!

I am trying to setup Postfix for the first time (have used Sendmail
only in the past) and I am running into a slight problem. Mainly, I
need to have this server, foobar.A.com, (which it is the MX record for
A.com domain) to "only" receive email for the A.com domain and 'pass
it' to the final server (running Exchange, exchange.A.com). At the same
time, I want it to "only" accept outbound from the Exchange
(exchange.A.com) server as well.

How should my main.cf look? Thank you in advance.

David Collantes wrote:
> HI there!
>
> I am trying to setup Postfix for the first time (have used Sendmail
> only in the past) and I am running into a slight problem. Mainly, I
> need to have this server, foobar.A.com, (which it is the MX record for
> A.com domain) to "only" receive email for the A.com domain and 'pass
> it' to the final server (running Exchange, exchange.A.com). At the same
> time, I want it to "only" accept outbound from the Exchange
> (exchange.A.com) server as well.
>
> How should my main.cf look? Thank you in advance.

The "mynetworks" parameter is used to specify the hosts that
are trusted to send outgoing email. Assuming the IP address of
exchange.a.com is 1.2.3.4, then it would look like this:

mynetworks = 127.0.0.1, 1.2.3.4
relay_domains = a.com
transport_maps = hash:/etc/postfix/transport
address_verify_relayhost = exchange.a.com

--< /etc/postfix/transport >--
a.com smtp:[1.2.3.4]
--or--
a.com smtp:[exchange.a.com]


--
Greg

Greg Hackney wrote:
> David Collantes wrote:
> > HI there!
> >
> > I am trying to setup Postfix for the first time (have used Sendmail
> > only in the past) and I am running into a slight problem. Mainly, I
> > need to have this server, foobar.A.com, (which it is the MX record for
> > A.com domain) to "only" receive email for the A.com domain and 'pass
> > it' to the final server (running Exchange, exchange.A.com). At the same
> > time, I want it to "only" accept outbound from the Exchange
> > (exchange.A.com) server as well.
> >
> > How should my main.cf look? Thank you in advance.
>
> The "mynetworks" parameter is used to specify the hosts that
> are trusted to send outgoing email. Assuming the IP address of
> exchange.a.com is 1.2.3.4, then it would look like this:
>
> mynetworks = 127.0.0.1, 1.2.3.4
> relay_domains = a.com
> transport_maps = hash:/etc/postfix/transport
> address_verify_relayhost = exchange.a.com
>
> --< /etc/postfix/transport >--
> a.com smtp:[1.2.3.4]
> --or--
> a.com smtp:[exchange.a.com]

Excellent Greg, thank you so much!!!