Reverse DNS - mail error

[Ion-Mihai Tetcu]

[ 72 chars / line, please ]


On Thu, 11 Mar 2004 13:42:56 +0200
"Gareth Bailey" <freebsd at xiplan.com> wrote:

> My postfix seems to be running just fine, but i recently had a problem
> sending mail to a particular address. The message sent to me, the
> postmaster, was:
> 
> host <IP Number>
>     said: The server sending your mail [<IP Number>] does not have a
>     reverse DNS entry. Connection Rejected. Please contact your
>     Dial-Up/DSL/Network ISP Provider. Default Reject! (in reply to end
>     of DATA command)
> 
> What does this mean and what do i need to do?
> Any info will be much appreciated

Some think this is an anti-spam measure.

Well, you need to have a PTR from your ip to the domain name in adition
of the A record that points the domain name to the ip, e.g.:
<IP Number>.in-addr.arpa.  1D IN PTR  domain.of.mail.smtp.server

For that you should probably ask you ISP or use something like
DynDNS.org or no-ip.com (if you get the ip dynamically).


BTW, i don't see what's the use of hiding the ip in question, since you
gain nothing in terms of security from this and we cannot investigate
what DNS servers are returning for the ip, not knowing it

-- 
IOnut
Unregistered ;) FreeBSD user