[CentOS] help from community

Thu Apr 12 11:35:07 UTC 2012
Peter Peltonen <peter.peltonen at gmail.com>

Hi,

On Thu, Apr 12, 2012 at 2:29 PM, Prabhpal S. Mavi
<prabhpal at digital-infotech.net> wrote:
> it is something out of control, because it is not my problem. Our server
> has all record created (A,MX,PTR,SPF etc). i have three relay hosts fully
> functional. destination server is not accepting from any relay host.

Looking at the error msg briefly I think the problem is with the DNS records:

> rejected: cannot find your hostname, [205.234.223.198] (in reply to RCPT
> TO command) (in reply to RCPT TO command))

$ host 205.234.223.198
198.223.234.205.in-addr.arpa domain name pointer mx4.servershost.net.

$ host mx4.servershost.net
mx4.servershost.net has address 66.225.237.241

As you can see the DNS resolves to different IP address than given by
the PTR record. Some email systems consider this as an indication of a
misconfigured mail server (spam sending attempt) and refuse to relay.

Best,
Peter