Who else does not get mail notifications ... [solved]

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ingo2
Posts: 81
Joined: 06 Feb 2012, 10:32

Who else does not get mail notifications ... [solved]

Post by ingo2 » 31 Jul 2013, 16:10

Since about 1/2 year I do not receive any mail notifications on postings/threads I habe subscribed to and about PD's.

Meanwhile I was able to dig for the root cause togetrher with ["johannes"] and found:

my mail provider (GMX) refuses to accept the mail from the forum's mail-server. The reason seems to be that here in Germany at least GMX and WEB.de perform a "reverse DNS lookup" (https://en.wikipedia.org/wiki/Reverse_DNS_lookup) for the delivering server to reduce spam load (and in fact it is efficient). The forum server logs following:
Jul 24 08:30:37 public postfix/smtp[25457]: 9226E9868D: host
mx00.gmx.net[213.165.67.99] refused to talk to me: 554-gmx.net (mxgmx010)
Nemesis ESMTP Service not available 554-No SMTP service 554 invalid DNS
PTR resource record
I have checked the header of such a mail which carries a local IP address for the sender of forum mail.

I digged out an old notification from May 2012 where Exito's mail server
was different and all worked fine. Here the important part form that
mail-header:

.... snip ....
Received: (qmail invoked by alias); 08 May 2012 07:35:54 -0000
Received: from mail.excito.net (EHLO excitohb.cust.ipeer.se)
[213.180.84.211]
by mx0.gmx.net (mx025) with SMTP; 08 May 2012 09:35:54 +0200
Received: from excitohb.cust.ipeer.se (localhost.localdomain [127.0.0.1])
by excitohb.cust.ipeer.se (Postfix) with ESMTP id 12A4C3A21624
for <ingo-xyz@gmx.net>; Tue, 8 May 2012 09:35:52 +0200 (CEST)
Subject:
...... snip ........

And now you can clearly see the sender is:

"mail.excito.net" with IP = 213.180.84.211.

Checking the reverse DNS lookup:

Code: Select all

dig PTR -x 213.180.84.211
results in "mail.excito.net".

So at that time all was fine and now it fails because of 2 things:
1. forum's mail server has a private/local IP address
2. IP and hostname do not match and cannot be reverse resolved.

So I wonder if I (with GMX and/or WEB.de as mail provider) am the only one not receiving mails from the forum anymore???

This can only be solved by Exito by delivering the mails though an officially approved mail server.

Best regards,
Ingo
Last edited by ingo2 on 09 Aug 2013, 11:04, edited 2 times in total.
UNIX is user friendly, it's just picky about who its friends are.

RandomUsername
Posts: 904
Joined: 09 Oct 2009, 18:49

Re: Who else does not get mail notifications from the forum?

Post by RandomUsername » 31 Jul 2013, 16:21

I receive them OK but I am hosting my own mail server on the B3.
This can only be solved by Exito by delivering the mails though an officially approved mail server.
By who's definition would it be officially approved? The Internet police? ;)

ingo2
Posts: 81
Joined: 06 Feb 2012, 10:32

Re: Who else does not get mail notifications from the forum?

Post by ingo2 » 31 Jul 2013, 16:48

This can only be solved by Exito by delivering the mails though an officially approved mail server.
By who's definition would it be officially approved? The Internet police? ;)[/quote]

Yes the NSA ;-)

As explained above the (to i.e. to GMX) delivering server must have a DNS-registered hostname and its IP must reverse resolve to that hostname - that's all.

Ingo
UNIX is user friendly, it's just picky about who its friends are.

Ubi
Posts: 1547
Joined: 17 Jul 2007, 09:01

Re: Who else does not get mail notifications from the forum?

Post by Ubi » 01 Aug 2013, 02:23

ingo2 wrote: its IP must reverse resolve to that hostname
Theres nothing "official" about that restriction, and there is fortunately no government "approving" how a mail server "must" work. In fact, theres so many legitimate mail servers that do not have reverse dns set, that setting this rule is more trouble than it solves. As you are experiencing right now.

ingo2
Posts: 81
Joined: 06 Feb 2012, 10:32

Re: Who else does not get mail notifications from the forum?

Post by ingo2 » 01 Aug 2013, 14:08

Ubi wrote:
ingo2 wrote: its IP must reverse resolve to that hostname
Theres nothing "official" about that restriction, ...
That's absolutely correct. But plase look here http://www.linuxmagic.com/best_practice ... e_dns.html and see that it is good practice at least.

And in fact, it significantly reduced the spam in my mailbox since GMX is checking reverse-DNS resolution. So my only whish is that I receive e-mail notifications with my existing mail-account. I therefore just ask for a reverse-dns entry for the forum's mail server.

Best regards,
Ingo
UNIX is user friendly, it's just picky about who its friends are.

ingo2
Posts: 81
Joined: 06 Feb 2012, 10:32

Re: Who else does not get mail notifications from the forum?

Post by ingo2 » 07 Aug 2013, 13:46

Seems you are trying to fix it or even succeeded.

Got a notification today (Aug. 7.) which dates back to Aug. 2. Here the header:

Code: Select all

From - Wed Aug  7 17:11:47 2013
X-Account-Key: account1
X-UIDL: 0LsPbw-1W8yIK19ia-011yih
X-Mozilla-Status: 0001
X-Mozilla-Status2: 00000000
X-Mozilla-Keys:                                                                                 
Return-Path: forum@excito.com
Received:  from public.excito.org ([31.216.38.81]) by mx-ha.gmx.net (mxgmx112)
 with ESMTP (Nemesis) id 0LsPbw-1W8yIK19ia-011yih for <ingo-xyz@gmx.net>;
 Wed, 07 Aug 2013 16:55:36 +0200
Received: from public.excito.org (localhost [127.0.0.1])
	by public.excito.org (Postfix) with ESMTP id A5D8998550
	for <ingo-xyz@gmx.net>; Fri,  2 Aug 2013 15:45:41 +0000 (UTC)
Subject: =?UTF-8?B?VG9waWMgcmVwbHkgbm90aWZpY2F0aW9uIC0gIlJlbGVhc2Ugbm90ZXMgZm9y?=
 =?UTF-8?B?IEV4Y2l0byBCdWJiYSAyJjMgc29mdHdhcmUgdmVyc2lvbiAyLjYi?=
To: =?UTF-8?B?aW5nbzI=?= <ingo-xyz@gmx.net>
From: <forum@excito.com>
Reply-To: <forum@excito.com>
Sender: <forum@excito.com>
MIME-Version: 1.0
Message-ID: <e44dc9e36931eda90008389a5a634695@forum.excito.net>
Date: Fri, 02 Aug 2013 15:40:29 +0000
Content-Type: text/plain; charset=UTF-8
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: phpBB3
X-MimeOLE: phpBB3
X-phpBB-Origin: phpbb://forum.excito.net
Content-Transfer-Encoding: quoted-printable
Envelope-To: <ingo-xyz@gmx.net>
X-GMX-Antispam: 0 (Mail was not recognized as spam); Detail=V3;
X-GMX-Antivirus: 0 (no virus found)
This mail was delivered via Server "public.excito.org" which has a reverse DNS entry:

Code: Select all

dig PTR -x 31.216.38.81
....
;; ANSWER SECTION:
81.38.216.31.in-addr.arpa. 3600	IN	PTR	public.excito.org.
Last edited by ingo2 on 07 Aug 2013, 15:15, edited 1 time in total.
UNIX is user friendly, it's just picky about who its friends are.

Ubi
Posts: 1547
Joined: 17 Jul 2007, 09:01

Re: Who else does not get mail notifications from the forum?

Post by Ubi » 07 Aug 2013, 15:11

Yes, the reverse dns has been fixed this afternoon so that it matches the primary hostname of the forum server. Good to see that this fixes the problems you were facing

ingo2
Posts: 81
Joined: 06 Feb 2012, 10:32

Re: Who else does not get mail notifications from the forum?

Post by ingo2 » 07 Aug 2013, 16:32

Geat - many thanks!

I just got the notification on Ubi's post, so all is fine!

Best regards,
Ingo
UNIX is user friendly, it's just picky about who its friends are.

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