On Thu, Nov 06, 2014 at 09:42:56AM +0100, Heiko Schlittermann wrote: > They refuse to accept mails from our systems: > > SMTP error from remote mail server after initial connection: > host mx01.kundenserver.de [212.227.17.191]: 554-kundenserver.de > (mxeue006) Nemesis ESMTP Service not available > 554-No SMTP service > 554 invalid DNS PTR resource record, IP=212.80.235.156 ... > Is there anybody with any good idea?
I'm sure that kundenserver.de uses self-written poor software that can't handle CNAMEs on PTRs. Proof: 554-kundenserver.de (mxeue005) Nemesis ESMTP Service not available 554-No SMTP service 554 invalid DNS PTR resource record, IP=91.207.115.113 554-kundenserver.de (mxeue003) Nemesis ESMTP Service not available 554-No SMTP service 554 invalid DNS PTR resource record, IP=80.252.139.1 554-kundenserver.de (mxeue005) Nemesis ESMTP Service not available 554-No SMTP service 554 invalid DNS PTR resource record, IP=62.176.2.83 Standart resolver libraries in popular OSes are capable for this feature since millenium, or even 1996-1997... Nowadays only self-written resolver could be confused by CNAME. :) I think this behaviour contradicts common practice, so this is a bug. -- Eugene Berdnikov -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
