[Mailman-Users] emails from mailman rejected with error "reject=550 Relaying denied. IP name possibly forged"

[Abdullah AL-Maskari]

Hi,

thanks for your reply.

I should have probably mentioned that I have another instance of mailman 
running on another server on the network and it is not having any 
trouble sending mail through mailhost. The sendmail files I am using for 
my mailman installation have been copied from the other server as the 
whole idea is to migrate from the currently working server to the one I 
built.

I will look at the spam filter configurations and my DNS but I dont see 
how any of those systems could be broken if the original mailman server 
is working fine.


Thanks
Abdullah
On 27/07/2014 00:54, Stephen J. Turnbull wrote:
> Abdullah Maskari writes:
>
>   > Jul 24 09:09:16 mailhost sm-mta[3309]: s6O89FAL003309:
>   > ruleset=check_rcpt, arg1=<target-address at external.domain2.com>,
>   > relay=mailhost.server.in-dmz.on.internal-domain.com [mailhost ip
>   > address] (may be forged), reject=550 5.7.1
>   > <target-address at external.domain2.com>... Relaying denied. IP name
>   > possibly forged [mailhost ip address]
>
> Looks to me like your DNS is quite broken (the references to IP
> addresses being forged).  Many destination hosts will filter such
> mail.
>
> The enhanced status code is 5.7.1, an administrative reject.  You've
> violated somebody's spam-filtering policy, and they're not accepting
> mail from you.  You might want to check if your IP address(es) are on
> a blackhole list.
>
> However, I think the immediate priority is fixing your DNS so that
> your external mail server is the MX for your domain, which has a
> proper A and/or AAAA address (ie, the domain name advertised is not a
> CNAME), and has PTR record from the MX name to the server's IP.
>