At 13:17 +0200 2003/03/30, Nico Erfurth wrote: >On Sun, 30 Mar 2003, Giuliano Gavazzi wrote: [...] > > I then perfected this by checking the direct DNS of the helo arg
>> against the ip of the host, if the reverse DNS check failed. I
> > consider this an RFC enforcement. [...] >And again, this isn't a perfect solution, what about hosts with two
>outgoing interfaces?
>
>primary_hostname is set to the hostname of the first interface, but
>sometimes the host sends with the second interface (I think this isn't
>very unusual).
I guess, it makes sense if the two interfaces are on different
networks (on distinct internet connections). In this case the DNS of
primary_hostname could point to both addresses. I do not know in what
format would an exim dns lookup for an A record, but if it returns
all addresses one could still check that one matches the client host
address.
