Am 17.02.2018 um 16:15 schrieb tech-lists via Exim-users: > An IP *cannot* resolve to a CNAME as per RFC 1034. It must resolve to an
> A-record, hence the error "reverse dns failure".
>
CNAME PTR Chains are totally normal, due to the fact, that small
providers in science centers get those CNAME PTRs
as a possibility to have theire own nameservers without the need of a
real owned network @ i.e. ripe.
And no standard software i meet, did have problems with it. If there
were problems, it was home grown software,
or failing DNS caches.
