How to set Firewall for sendmail?

[Paul Howarth]

On Wed, 2005-07-06 at 15:01 -0700, Don wrote:
> At 11:50 AM 7/6/2005, you wrote:
> >Am Mi, den 06.07.2005 schrieb Don um 20:42:
> >
> > > Thanks that worked, but now I have a relaying problem.  I have two 
> > systems,
> > > a.domain.com b.domain.com.  How do I allow a to relay thur b?
> > > Don
> >
> >Please read the docs.
> >
> >http://www.sendmail.org/~ca/email/relayingdenied.html
> >http://www.sendmail.org/m4/anti_spam.html
> >
> >Maybe it makes sense to configure b.domain.com the smart_host in the MTA
> >of a.domain.com. In the access_db of b.domain.com's Sendmail you need to
> >set a rule like
> >
> >Connect:a.domain.com       RELAY
> >Connect:<IP of a>                RELAY
> >
> >Alexander
> >
> Thanks - I got it working by modifying the relay-domians file.  Also found 
> this example http://www.freebsddiary.org/relay.php

The relay-domains file is really intended for when your mail server is
acting as a backup or intermediate MX host for a domain, not for
outgoing mail. Alexander's suggestion above is the "right" way of
configuring b.domain.com's sendmail to relay mail for a.domain.com.

Paul.
-- 
Paul Howarth <paul at city-fan.org>