[Mailman-Users] Users complain, they don't receive mails from the list

[Mark Sapiro]

On 01/25/2016 03:27 PM, Sascha Rissel wrote:
> Hi Mark!
> 
>> In simple terms, it claims your mail server is not properly configured.
>> I don't know what your Mailman server's domain name is, but it appears
>> from the error message that its IP is 62.75.175.182 and that IP has an
>> rDNS PTR record to euve51864.serverprofi24.de.
> 
> this is all pretty correct.
> 
> "euve51864.serverprofi24.de" is the natural name of the vServer, I am
> running.
> I don't have a real domain configured, since I mainly just use it for
> mailman.


As I indicated in a follow-up post web.de is apparently not allowing
'generic' domains any more.


> I configured all Mailman lists to use something like <list name>@rc-worms.de,
> where <rc-worms.de> is the www domain of my sports club, whose
> administrator I am.
> For better readability I named and configured all lists this way, to use <
> members at rc-worms.de>, <team1 at rc-worms.de> as exlicity reply-to address and
> so on.
> 
> This worked pretty well for years.
> Did it now turn into a problem, that reply-to address and domain () bear a
> different IP/rDNS result?


That is not the problem as far as I can tell. The problem is that the
specific domain you are using for your mail server,
euve51864.serverprofi24.de, is now seen as a 'generic' name and is not
acceptable to web.de.


> Is there something you could suggest in this case?
> 
> Should I maybe configure a subdomain on my vServer, like <lists.rc-worms.de>,
> from which the mails will be send from and can bear own DNS config?


Yes. lists.rc-worms.de should be good. I would have suggested just
rc-worms.de, but that already has an A record pointing to a different
server.

The issue you will run into is that while you can configure the MTA to
identify itself as lists.rc-worms.de and you can create the A record for
it, you don't control the rDNS PTR record for 62.75.175.182. That's
controlled by intergenia.de. It may be no problem to get them to change
it, but it could be a stumbling block. You'll find out when you ask.

With respect to the underlying issue here, ISPs are getting more and
more fussy about only accepting mail from what they consider to be real
mail servers. Trying to run a mail server with a dynamic IP or an IP
with a 'generic' host name is just not possible if you want reliable
acceptance of your mail.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan