Postfix-Server behind a DSL-Router

[Bala Vishwanathan Iyer]

Dear Mr. Kruppa

you need create nat rule in your Netgear Router where in you specify
that your external ip address in your case 217.92.171.227 map to your
fedora box which is let us say 192.168.10.4 or 192.168.10.5. Since
SMTP would look for an actual server than just any machine whcih has
port 25 forwarding enabled.

Regards
Bala V Iyer

On Thu, Apr 9, 2015 at 5:28 PM, Peter Ulrich Kruppa
<pukruppa at googlemail.com> wrote:
> Hello!
>
> Am 09.04.2015 um 13:20 schrieb Bala Vishwanathan Iyer:
>>
>> Dear Mr. Kruppa
>>
>> I have some futher querries :-
>>
>> 1. Is this server your mail server for your domain. meaning does the
>> mail exchange record for your domain point to this server or some
>> other server.
>>
>> In case it it pointing to some other server say Google mail server or
>> any other hosting provider. Then I would suggest you install something
>> like fetch mail to get mails fro your mail server to your postfix
>> server.
>
> I believe that is what Frank Elsner was so nice to test from "outside"
>         # host -t mx pukruppa.de
>         pukruppa.de mail is handled by 10 mail.pukruppa.de.
>         # telnet mail.pukruppa.de 25
>         Trying 217.92.171.227...
>         telnet: connect to address 217.92.171.227: Connection timed out
>
>
>> 2. can you telnet your postfix servers external ip on port 25 from
>> outside your network.
>>
>> If no, then that is the issue.
>
> Yes, but what can I do? port 25 seems to point to my Fedora box.
>
> Regards
>
> Peter Kruppa
>
>>
>> Regards
>> Bala V Iyer
>>
>> On Thu, Apr 9, 2015 at 3:37 PM, Peter Ulrich Kruppa
>> <pukruppa at googlemail.com> wrote:
>>>
>>> Hi everyone,
>>>
>>> please do excuse my unspecific subject - I don't really know what my
>>> problem is yet.
>>>
>>> I set up a Postfix-Server on my Fedora 21 box, which is connected to
>>> the internet via
>>> some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora
>>> box fixed on
>>> 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's
>>> say for
>>> mydomain.com .
>>>
>>> Now I can
>>>    - send myself mails from my Fedora box
>>>    - send mails from my Fedora box to the outside p. ex. my googlemail
>>> account
>>>
>>> but I can't receive mails from outside.
>>>
>>> When I do a
>>>      # tcpdump -n -i any tcp port 25
>>> on my Fedora I can see many messsages like
>>>
>>> 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S],
>>> seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143
>>> ecr 0,nop,wscale 9], length 0
>>> 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S],
>>> seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393
>>> ecr 0,nop,wscale 9], length 0
>>> [...]
>>>
>>> Any good ideas, what else I can do to analyze my problem?
>>>
>>> Thanks for your answers
>>>
>>> Peter
>>> --
>>> users mailing list
>>> users at lists.fedoraproject.org
>>> To unsubscribe or change subscription options:
>>> https://admin.fedoraproject.org/mailman/listinfo/users
>>> Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
>>> Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
>>> Have a question? Ask away: http://ask.fedoraproject.org
>
> --
> users mailing list
> users at lists.fedoraproject.org
> To unsubscribe or change subscription options:
> https://admin.fedoraproject.org/mailman/listinfo/users
> Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
> Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
> Have a question? Ask away: http://ask.fedoraproject.org