> > FWIW it is hard to get sendmail to put in the address of the interface
> > on which the email is beig sent.  The address of its main interface
> > may not be in a publically visible DNS (eg if it is a 192.168.x.x address)
> > Doing so (look at the headers for this mail) means that the systems
> > actual name is completely absent.
> 
> Actually, that's really easy:
> O DaemonPortOptions=Family=inet, address=0.0.0.0, Name=MTA
> O DaemonPortOptions=Family=inet6, address=::, Name=MTA6, Modifiers=O
> #O ClientPortOptions=Address=0.0.0.0

I think you will find that the above makes it put in the address of
the systems main interface at the time sendmail is started.

> If a server tells me that it's address is 192.168.something, I certainly
> do want to drop that server's email as spam.

Probably true - but maybe not, it could be someone behind a NAT relay.

> > Checking for the MX record (ie requiring that the outbound mail gateway
> > is the same is the inward one) will surely lead to incorrect bounces.
> 
> That's why I don't want to do that. I want to check A AND MX records; the
> name which is given should be a working address in one of the two sets of
> addresses.

Do you mean you want to find an A record and an MX record, or an A record or
and MX record?  Hoping for the former is rather pointless.

In any case the only MX record for host.subdomain@domain is likely to
be for domain, and very likely to point somewhere entirely different.

Even if I sent my outward mail via my ISPs mail relay, you wouldn't get
an MX match.  I don't send it that way because their relay is often down
(and in any case it gets blacklisted along with all the dialup addresses).

	David

-- 
David Laight: david@l8s.co.uk