Re: [exim4] Testing and making sense of smtp output
On Mon 13 Oct 2014 at 04:06:27 +0200, lee wrote:
> Harry Putnam <reader@newsguy.com> writes:
>
> > lee <lee@yagibdah.de> writes:
> >
> > [...]
> >
> > Thanks for the tips.
> >
> >>> SMTP>> EHLO 2xd
> >
> >> That's an invalid helo string.
> >
> > Is a valid one made up of just the full fqdn?
>
> See https://tools.ietf.org/html/rfc2821#section-4.1.1.1
>
> It says to either use the fqdn or, if not possible, an IP
> literal. However, it's common practise to deny IP addresses in HELO
> greatings.
An address literal is not the same as an IP address. An MTA should not
be rejecting mail on the basis that the HELO is an address literal.
It's probably academic what the HELO is most of the time. Many ISPs
will accept any old rubbish for it.
Reply to: