Setting up PTR SMTP rDNS

Tanker

Member
Apr 25, 2019
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I have setup a domain in a dedicated server for sending mass-mail everything seems to be ok, I can send no problem... everything seems to be ok, BUT!...

the server is has been set up with a primary domain lets call it, `foo.com` and the server that send the emails lets call it `faa.com`, `foo.com` isn't use for anything else that to be setup for the dedicated server with a `WHM`, the second domain `faa.com` has its own `cPanel` account inside the server.

When using the website `mxToolsBox.com` it shows that the domain `faa.com` is missing `SMTP Banner Mismatch` and that is the only error that I got.

The more I read about this the more I get confuse some say that my main domain `foo.com` has to have a `rDNS` which it does have, some others say that I need to have a `SPF1` which is already set up, some other `DMCA` which I also have... I don't know how one can be related to other but I have it ready and ok when testing.

The PTR: `mxToolBox.com` say that
It is best practice to put the name of your server in your SMTP banner so that anybody who connects via your IP Address has a clue as to who they are talking to. You will get this warning if the name you present yourself as is not in the same domain as the hostname we get when we perform a PTR lookup on your IP Address.
And this is whats confuses me... is this a DNS zone that I need to register at `faa.com` domain? if so where?, MX zone?, PTR? if PTR what values do I need to use?
say that my host name is `1-2-3-4.foo.com` and my PTR is `3.2.1.in-addr.arpa.` and the value is `1-2-3-4.foo.com` then what info/zone do I need to register for this domain `faa.com`?

The more I read the more confuse I get...

Can someone please explain to me this in a very simple way how can I set this up.
please!
Thank you in advance!
 

Tanker

Member
Apr 25, 2019
6
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3
México
cPanel Access Level
Root Administrator
Hey there! If I'm following all that correctly...by default all mail will have the server's hostname. You want the rDNS for the main IP address to match the server's hostname. Is that already set up?
Yes, that has been set up to the main domain foo.com the domain that sends the emails is another domain faa.com which is in the same WHM as foo.com, when I go to mxtookbox.com and run a test for faa.com this is what I got: See image in my WHM panel at Home »Email »Email Deliverability everything checks valid, in one of my bounce back emails I contacted the webmaster for that particular bounceback this is what they told me:

| A mail server's IP address must have an FQDN (PTR-Record, rDNS) in a
| domain that belongs to the operator of this mail server. This FQDN must
| terminate at the same IP address (A record). (You can find details in
| RFC 1912 and the Wikipedia article on FcrDNS.)
|
| In particular, we recommend choosing a host name that indicates its
| usage as a mail server (eg. mail.example.com) and >>> to ensure the host's
| domain leads to a website providing full contact details. <<<
Would you mind if I send you the server and real domain specification in a PM?
I can then post the solution for every one else to see that migh have the same problem...
Thank you.
 

cPRex

Jurassic Moderator
Staff member
Oct 19, 2014
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It would be best to create a ticket for that so our team can do some troubleshooting directly on the server if necessary. If you do that, please post the ticket number here so I can follow along and I'll be sure to keep this thread updated with our findings.
 

Tanker

Member
Apr 25, 2019
6
2
3
México
cPanel Access Level
Root Administrator
It would be best to create a ticket for that so our team can do some troubleshooting directly on the server if necessary. If you do that, please post the ticket number here so I can follow along and I'll be sure to keep this thread updated with our findings.
Thank you. the ticket number is: 94311133
 

Tanker

Member
Apr 25, 2019
6
2
3
México
cPanel Access Level
Root Administrator
After some troubleshooting, our team was able to confirm that rDNS was set up correctly and there is no issue with the server's configuration, and we recommended you contact the provider experiencing issues.
Hello, the cPanel team has confirm that everything on my server has been set up properly for the use intended, I have also contacted the TMobile network to review my case(just today) with the result from the cPanel Team, I expect a reply within the next 12hr...

I can't thank you guys enough, I'll keep you updated on this matter....
 
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