tech-lists via Exim-users <exim-users@???> (Sa 17 Feb 2018 16:15:41 CET):
> On 16/02/2018 12:34, Heiko Schlittermann via Exim-users wrote:
> > Hi
> >
> > some you (j*.e@t*.de) responded, but I can't answer:
> >
> > j*.e*@t*.de
> >
> > host mail.t*.de [*.*.230]
> > SMTP error from remote mail server after RCPT
> > TO:<j*.e*@t*.de>:
> > 550 Client host rejected: reverse DNS failure-1
> >
> > I'm quite sure that my IP 84.19.194.3 resolves.
> > Yes, it resolves to a CNAME, but this shouldn't be a problem.
> >
> > J*, do you have some other mean of contact?
> > Or can you, for this communication, whitelist my server 84.19.194.3?
>
>
> An IP *cannot* resolve to a CNAME as per RFC 1034. It must resolve to an
> A-record, hence the error "reverse dns failure".
We followed
https://tools.ietf.org/html/rfc2317
Where is the "must resolve to…" stated?
--
Heiko
