Mailing List CGatePro@mail.stalker.com Message #103689
From: Urs Grützner <ugruetzner@ems.ch>
Subject: Re: RDNS (Reverse lookup) failure
Date: Mon, 5 Nov 2012 19:05:52 +0100
To: CommuniGate Pro Discussions <CGatePro@mail.stalker.com>
X-Mailer: Apple Mail (2.1084)
Thanks for your help

In fact 194.209.14.153 is inbound and outbound as well. 

Of course, as 194.209.14.146 is the Gateway of our LAN, every mail passes this IP as well. But its origin should be 194.209.14.153.


I do not understand the mechanism, when and how this Gateway IP  is attributed and sent with mail. And why not the mail servers IP???


The weird thing is: before we switched to our new provider this did not happen. Except that Router, IPs and DNS have changed, everything should work analogously.


At the moment I have a workaround, that I can send my SMTP in relay with the SMTP of our Provider Swisscom. This "whiteswashes" the fact, that our reverse is not correct.

But thats not a solution. I want that the 194.209.14.153 is sent with the mail. (The reverse lookup to 194.209.14.146 might help as well but I am not happy with that trick as soon as I did not understand the mechanism) ;-)



Thanks


Urs




From:Lyle Giese <lyle@lcrcomputer.net>
Subject:Re: RDNS (Reverse lookup) failure
Date:Mon, 05 Nov 2012 11:06:39 -0600
To:CommuniGate Pro Discussions <CGatePro@mail.stalker.com>
It looks to me like 194.209.14.153 is for inbound email, while outbound email is forwarded via 194.209.14.146.  

194.209.14.146 does not have a reverse lookup.  This ip address does not appear to be accepting inbound email so I can not verify the HELO/EHLO greeting it may be providing.  

I think you need to get a reverse installed for 194.209.14.146 with the greeting used by that machine.

Lyle Giese
LCR Computer Services, Inc.

On 11/5/2012 10:07 AM, Urs Grützner wrote:
We have changed our Internet provider, needed to change also the DNS authority and the IP's.

The new zone file on the Master DNS is ok, according to the rules.  

The name Server IPS on the Server are changed to the new provider.

Our server is behind a Firewall, with local IPs 10.0.88.100, 127.0.0.1,


The forward and reverse lookup for ems.chmail.ems.ch and the public IP 194.209.14.153 are OK (see lookups below)







Now we have the following problem:

When sending mails its not the IP of our server which is transmitted, but the IP of our Gateway. Of course the RDNS lookup will fail for servers, which perform this check. 


I do not know how this IP is forwarded with mail. How does the mail server get his own public IP? By checking the DNS?  I don't understand how the gateway IP is coming into the header


Any help is appreciated

Thanks

Urs


PS: Here is a mail I have sent from the concerned server ems.ch. One can see the gateway number as the origin, instead of the mail servers IP number



Von:  Urs Grützner <ugruetzner@ems.ch>

Betreff:  test WAN IP

Datum:  5. November 2012 12:47:33 MEZ

An:  Gruetzner Urs <ursg@mac.com>

Return-Path:  <ugruetzner@ems.ch>

Received:  from st11b01mm-smtpin208.mac.com ([17.172.48.39]) by ms02551.mac.com (Oracle Communications Messaging Server 7u4-26.01 (7.0.4.26.0) 64bit (built Jul 13 2012)) with ESMTP id <0MD0006J5JFCOZA1@ms02551.mac.com> for ursg@mac.com; Mon, 05 Nov 2012 11:47:36 +0000 (GMT)

Received:  from ems.ch ([194.209.14.146]) by st11b01mm-smtpin208.mac.com (Oracle Communications Messaging Server 7u4-23.01(7.0.4.23.0) 64bit (built Aug 10 2011)) with ESMTP id <0MD00043QJFAL170@st11b01mm-smtpin208.mac.com> for ursg@mac.com (ORCPT ursg@mac.com); Mon, 05 Nov 2012 11:47:36 +0000 (GMT)

Received:  from [10.0.99.54] (account ugruetzner [10.0.99.54] verified) by ems.ch (CommuniGate Pro SMTP 5.1.16) with ESMTPSA id 4681822 for ursg@mac.com; Mon, 05 Nov 2012 12:47:33 +0100




„Lookup“ wurde gestartet …


; <<>> DiG 9.6-ESV-R4-P3 <<>> ems.ch any +multiline +nocomments +nocmd +noquestion +nostats +search
;; global options: +cmd
ems.ch. 3600 IN MX 10 mail.ems.ch.
ems.ch. 3600 IN A 194.209.14.153
2012103001 ; serial
10800      ; refresh (3 hours)
3600       ; retry (1 hour)
604800     ; expire (1 week)
21600      ; minimum (6 hours)
)
ems.ch. 687 IN NS ns2.ip-plus.net.
ems.ch. 687 IN NS ns1.ip-plus.net.
ems.ch. 687 IN NS ns2.ip-plus.net.
ems.ch. 687 IN NS ns1.ip-plus.net.
mail.ems.ch. 687 IN A 194.209.14.153
ns1.ip-plus.net. 19862 IN A 164.128.36.34
ns2.ip-plus.net. 1833 IN A 164.128.76.39



„Lookup“ wurde gestartet …


; <<>> DiG 9.6-ESV-R4-P3 <<>> mail.ems.ch any +multiline +nocomments +nocmd +noquestion +nostats +search
;; global options: +cmd
mail.ems.ch. 657 IN A 194.209.14.153
ems.ch. 657 IN NS ns1.ip-plus.net.
ems.ch. 657 IN NS ns2.ip-plus.net.
ns1.ip-plus.net. 19832 IN A 164.128.36.34
ns2.ip-plus.net. 1803 IN A 164.128.76.39


„Lookup“ wurde gestartet …


; <<>> DiG 9.6-ESV-R4-P3 <<>> -x 194.209.14.153 any +multiline +nocomments +nocmd +noquestion +nostats +search
;; global options: +cmd
153.14.209.194.in-addr.arpa. 86400 IN PTR mail.ems.ch.



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