Re: Sender IP reverse lookup rejected

2019-08-14 Thread Kadlecsik József
On Wed, 14 Aug 2019, Kadlecsik József wrote:

> It seems it's a persistent problem. I tried to contact the postmaster at 
> the other side but of course got the same reject. We'll try to contact 
> them via a third party.

Using a third party as a relay, I got the same error message. Maybe the 
whole address space of .hu is blocked and the error message is just 
misleading.

Best regards,
Jozsef
-
E-mail  : kad...@blackhole.kfki.hu, kadlecsik.joz...@wigner.mta.hu
PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
  H-1525 Budapest 114, POB. 49, Hungary

Re: Sender IP reverse lookup rejected

2019-08-14 Thread Kadlecsik József
On Wed, 14 Aug 2019, Wietse Venema wrote:

> Kadlecsik J?zsef:
> > It seems it's a persistent problem. I tried to contact the postmaster at 
> > the other side but of course got the same reject. We'll try to contact 
> > them via a third party.
> 
> In that case, try setting 
> 
>   -o inet_protocols=ipv4
> 
> (or ipv6) and see if it is a specific kind of DNS that is borked.

The MX of the domain has got IPv4 address only, so IPv6 is not used.

We have got such a special transport for sites with advertised IPv6 
addresses but broken IPv6 connection... 

Best regards,
Jozsef
-
E-mail  : kad...@blackhole.kfki.hu, kadlecsik.joz...@wigner.mta.hu
PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
  H-1525 Budapest 114, POB. 49, Hungary


Re: Sender IP reverse lookup rejected

2019-08-14 Thread Kadlecsik József
On Wed, 14 Aug 2019, Wietse Venema wrote:

> > One of our users reported a rejected email with the error code and 
> > message
> > 
> > Remote-MTA: dns; artemis.gat.com
> > Diagnostic-Code: smtp; 550 Sender IP reverse lookup rejected
> > 
> > We handle several domains with different outgoing smtp settings at 
> > multiple mail gateways:
> > 
> > # /etc/postfix/master.cf
> > wignersmtp   unix  -   -   y   -   -   smtp
> > -o smtp_bind_address=148.6.0.56
> > -o smtp_bind_address6=2001:738:5001::56
> > -o smtp_helo_name=smtp.wigner.mta.hu
> > -o syslog_name=postfix-wigner-smtp
> > 
> > # /etc/postfix/main.cf
> > default_transport = kfkismtp
> > sender_dependent_default_transport_maps =
> > hash:/etc/postfix/sender_transport
> > 
> > # /etc/postfix/sender_transport
> > @wigner.mta.hu  wignersmtp:
> > ...
> > 
> > The sender address was from the @wigner.mta.hu domain and the IPv4/IPv6 
> > addresses resolve to smtp.wigner.mta.hu. The HELO name is also explicitly 
> > set to this name. Using debug_peer_list I could verify that the wignersmtp 
> > transport setting is used for @wigner.mta.hu senders indeed.
> > 
> > So, what kind of incorrect setting can the "Sender IP reverse lookup 
> > rejected" error message be mean?
> 
> It could be the same problem as GMAIL, where they would do a hard reject 
> after a temporary error during reverse DNS lookup.
> 
> At the time (years ago) I just turned on "-o soft_bounce=yes" for those 
> deliveries, so that the email would be delivered later.
> 
> Of course, soft_bounce is not ideal; nowadays I would use
> smtp_delivery_status_filter to change the 5.*.* into 4.*.* for that
> specific server response. 
> 
> If the result of this is that mail stays in the queue, then 
> further investigation will be needed.

It seems it's a persistent problem. I tried to contact the postmaster at 
the other side but of course got the same reject. We'll try to contact 
them via a third party.

Thank you to remind me about smtp_delivery_status_filter, it can come 
handy in other cases!

Best regards,
Jozsef
-
E-mail  : kad...@blackhole.kfki.hu, kadlecsik.joz...@wigner.mta.hu
PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
  H-1525 Budapest 114, POB. 49, Hungary


Sender IP reverse lookup rejected

2019-08-14 Thread Kadlecsik József
Hello,

One of our users reported a rejected email with the error code and message

Remote-MTA: dns; artemis.gat.com
Diagnostic-Code: smtp; 550 Sender IP reverse lookup rejected

We handle several domains with different outgoing smtp settings at 
multiple mail gateways:

# /etc/postfix/master.cf
wignersmtp   unix  -   -   y   -   -   smtp
-o smtp_bind_address=148.6.0.56
-o smtp_bind_address6=2001:738:5001::56
-o smtp_helo_name=smtp.wigner.mta.hu
-o syslog_name=postfix-wigner-smtp

# /etc/postfix/main.cf
default_transport = kfkismtp
sender_dependent_default_transport_maps =
hash:/etc/postfix/sender_transport

# /etc/postfix/sender_transport
@wigner.mta.hu  wignersmtp:
...

The sender address was from the @wigner.mta.hu domain and the IPv4/IPv6 
addresses resolve to smtp.wigner.mta.hu. The HELO name is also explicitly 
set to this name. Using debug_peer_list I could verify that the wignersmtp 
transport setting is used for @wigner.mta.hu senders indeed.

So, what kind of incorrect setting can the "Sender IP reverse lookup 
rejected" error message be mean?

Best regards,
Jozsef
-
E-mail  : kad...@blackhole.kfki.hu, kadlecsik.joz...@wigner.mta.hu
PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
  H-1525 Budapest 114, POB. 49, Hungary