DNS Settings Multiple IP-Addresses

[SteffenM]

Hello,

I guess my question has been asked before but after a long search I couldn't find a solution that solves my problem.

3 or 4 months ago I have switched a domain from the servers default 1. IP to the (till then) unused 2. IP. So far so good.
Now my customer has (the first time) a problem sending mails to a special address. Error-Msg: "550 [1. server domain] is not allowed to send mail from [customer domain]"
I read that Plesk (qmail/postfix) sends every mail over the main IP-address of the server and I have to allow that via DNS configuration. But I found different answers of what I should do. Some say that I have to customize the SPF-entry, some say that there has to be an mx-entry for both IP-adresses...

So I configured the following DNS entries:
[customer domain]. ___ A ___ [2. IP]
mail.[customer domain]. ___ A ___ [2. IP]
mail2.[customer domain]. ___ A ___ [1. IP]
[customer domain]. ___ MX (10) ___ mail.[customer domain].
[customer domain]. ___ MX (20) ___ mail2.[customer domain].
[customer domain]. ___ TXT ___ v=spf1 +mx +a ip4:[1. IP] ip4:[2. IP] -all
(Also a few other default-entries)

mxtoolbox mx-check says that everything is allright:
SMTP Reverse Banner Check ___ OK - [2. IP] resolves to [server-id].stratoserver.net
SMTP Reverse DNS Mismatch ___ OK - Reverse DNS matches SMTP Banner
SMTP TLS ___ OK - Supports TLS.
SMTP Connection Time ___ 0.328 seconds - Good on Connection time
SMTP Open Relay ___ OK - Not an open relay.
SMTP Transaction Time ___ 1.154 seconds - Good on Transaction Time

But the mail to the special mail-address still throws the same error - also after a few hours after my last DNS-edit.

BTW: Our server is the primary DNS for the domain and there are Reverse-DNS-Entries for both IPs to the server.

Can anyone please help me out of this? What did I do wrong? Is there a tool online to test these settings so that I don't have to send a testmail?

Best regards,
Steffen

P.S.: I have also read that there is a way to patch qmail to use the IP configured for the domain to send mails but if possible I would like to avoid "hacking" around - the server runs well, there is only this one customer running on the 2. IP and till now they have only problems with this one mail-recipient. So I would prefere finding an easy solution.

 

[SteffenM]

Funktioniert!

Es hat tatsächlich nur Zeit gebraucht, bis die DNS-Änderungen Wirkung zeigten. 3-4 Stunden waren anscheinend nicht ausreichend. Als ich heute morgen noch einmal testete ging der Mailversand.

Jetzt würde mich trotzdem interessieren, ob mir jemand sagen kann, ob nun die beiden MX-Einträge der Schlüssel waren oder der SPF-Eintrag ausgereicht hätte.
Weiß das jemand?

Kennt jemand eine Testmethode für einen solchen Fall? MxToolbox scheint wohl nicht das passende Werkzeug zu sein, da dort von Anfang an keine Warnung auftauchte.

Gruß,
Steffen