On Thu, 21 Nov 2002, Matthew Byng-Maddick wrote:
> On Thu, Nov 21, 2002 at 09:15:48AM +0000, Philip Hazel wrote:
> > On Wed, 20 Nov 2002, Marcelo Moreira wrote:
> > > Then insert a MX entry like this:
> > > domain.com MX 15 10.10.6.70
> > NO, NO, NO, NO!
> > You should NEVER put an MX record like that into the public DNS.
> > Think about what will happen if a foreign host accesses those MX
> > records, and it has its own local network that is using 10.x.x.x
> > addresses. That is a disaster.
>
> Erm, worse than that, the RHS of an MX is the cost and then a canonical
> name. 10.10.6.70 is not a canonical name.
Er indeed. I should have posted a double rant instead of a single rant. :-)
1. An MX record MUST have a domain name as its RHS (not an IP address).
2. The IP address of the domain on the RHS of an MX record must NOT be
a private address.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.