bind and outgoing mail relay

[Gregory Hicks]

> Date: Wed, 29 Oct 2008 09:52:05 -0700
> From: Justin Pryzby <justinpryzby at users.sourceforge.net>
> To: bind-users at isc.org
> Subject: Re: bind and outgoing mail relay
> 
> On Wed, Oct 29, 2008 at 09:24:36AM -0700, Gregory Hicks wrote:
> > > I wonder if there's any way of using our local recursive server 
for
> > > forcing all locally-originating mail to go through a given mail 
hub.
> > > I suspect not?
> > 
> > Not via DNS.  The setup is with the sendmail.cf (or what ever config 
> > file you use).
> That doesn't *force* outgoing mail through the mailserver; I was
> looking for a way (perhaps) to get all MX queries to return our local
> server, but I think that's impossible...?

Not impossible. h2n provides a way to set the MX for hosts to whatever
you desire.  In your own domain (or domains that you control) of
course.  You cannot do anything about domains that you do not control.

But the "gateway" function of sendmail.cf will, in fact, force all mail
to be relayed through a 'gateway' host.  If your firewall settings are
correct and block all connection attempts from other than the
designated host, mail not going to the mail gateway won't get
delivered.

I think the "DG" macro specifies the "gateway out of our domain".
You'll also want to have one or more instances of the CI (IP addresses
in our domain) macro.

Regards,
Gregory Hicks

> 
> Justin
> 

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Gregory Hicks                           | Principal Systems Engineer
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