Email Deliverability - REVERSE DNS (PTR)

Jcats

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Just a heads up, this might not make that warning go away in cPanel, that new feature is terrible and never works so customers will complain all the time that there is a 'problem' when in fact there is no problem like rDNS being set properly.
 
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ImperialTrader

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Just a heads up, this might not make that warning go away in cPanel, that new feature is terrible and never works so customers will complain all the time that there is a 'problem' when in fact there is no problem like rDNS being set properly.
You are correct, they responded me that they are responsible for this limitation and they will remove it to fix the PTR record issue.
But now they are asking me a question to remove this limitation, and I don't know what I should say :)

Their question is: "Please provide more detail for the steps you have in place to avoid this account being implicated in sending of unwanted mail."
 

Jcats

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I mean, I can't really tell you what to say because I have no idea what you will be using it for ;) but just tell them generally what kind of emails are going to be sent out from the server, it won't be used as an open relay, all mailboxes will have strong passwords, running nightly malware scans to prevent malicious scripts from being able to send out spam, etc ..
 

ImperialTrader

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I mean, I can't really tell you what to say because I have no idea what you will be using it for ;) but just tell them generally what kind of emails are going to be sent out from the server, it won't be used as an open relay, all mailboxes will have strong passwords, running nightly malware scans to prevent malicious scripts from being able to send out spam, etc ..
Ok but that’s just talk not actions
Is there any options at WHM which preventing sending spam emails?
 

Jcats

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Yes look through Tweak Settings(Mail) and Exim Configuration Manager in WHM, just go through the settings, you will see useful ones like notifications and such.
 
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ImperialTrader

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Yes look through Tweak Settings(Mail) and Exim Configuration Manager in WHM, just go through the settings, you will see useful ones like notifications and such.
I have another question please if you don't mind :)

They asked me to create Elastic IP first to mapping to it because they can't configure the reverse DNS to the same static IP of my server (I don't know why but I did that).

My 1st server hostname (s1.domain.com) with IP (1.1.1.1) having a reverse DNS (10.10.10.10 >> mail.domain.com) .. that's fine & that's what I did with AWS.
But now, my 2nd server hostname (s2.domain.com) with IP (2.2.2.2), what DNS I should set for it?
Can I use the same DNS (mail.domain.com) too?
Or shall I use another DNS for example (s2.mail.domain.com)
 

cPanelLauren

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Just a heads up, this might not make that warning go away in cPanel, that new feature is terrible and never works so customers will complain all the time that there is a 'problem' when in fact there is no problem like rDNS being set properly.
The only time I've run into issues using this feature is when NAT routing is incorrectly configured, if you have some constructive suggestions on how to make this feature more beneficial I'd be happy to pass them on for you.


But now, my 2nd server hostname (s2.domain.com) with IP (2.2.2.2), what DNS I should set for it?
Do you mean what should you set for the PTR record (rDNS)? If the mail users here will be using the same mail server mail.domain.com and that's what you're using in your PTR record there shouldn't be an issue with this.
 

ImperialTrader

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Do you mean what should you set for the PTR record (rDNS)? If the mail users here will be using the same mail server mail.domain.com and that's what you're using in your PTR record there shouldn't be an issue with this.
I think it's better each server uses it's own mail server, so I should set for the first server (s1.mail.domain.com) and for the 2nd server (s2.mail.domain.com), that's better correct?
Do you know why they can't configure the reverse DNS to the same static IP of my server? and they asked me to create a new IP to do that rDNS?
 

cPanelLauren

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I think it's better each server uses it's own mail server, so I should set for the first server (s1.mail.domain.com) and for the 2nd server (s2.mail.domain.com), that's better correct?
If they'll have different hostnames and be separate, yes you do need to do a second PTR record for the second server.

Do you know why they can't configure the reverse DNS to the same static IP of my server? and they asked me to create a new IP to do that rDNS?
I do not, unfortunately, AWS has its own best practices for their networking.
 
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Jcats

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The only time I've run into issues using this feature is when NAT routing is incorrectly configured, if you have some constructive suggestions on how to make this feature more beneficial I'd be happy to pass them on for you.
It incorrectly states that an rDNS is not set when it in fact is, I just clicked on a random cPanel account and it says:

"There is no reverse DNS configured for the IP address (123.123.123.123) that the system uses to send this domain’s outgoing email. "

When there is, for sure, 100%, rDNS set on the mentioned IP. We get many tickets about it, just an annoying feature.
 

cPanelLauren

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It incorrectly states that an rDNS is not set when it in fact is, I just clicked on a random cPanel account and it says:

"There is no reverse DNS configured for the IP address (123.123.123.123) that the system uses to send this domain’s outgoing email. "

When there is, for sure, 100%, rDNS set on the mentioned IP. We get many tickets about it, just an annoying feature.
It sounds like the rDNS lookup isn't getting completed properly - can you tell me about the server's configuration - IP addresses/Networking specifically?

Another thing that I ran into is that from the cPanel UI you won't see if there is an rDNS conflict (like the hostname was changed but the PTR record wasn't updated) but within WHM>>Email>>Email Deliverability the issue is shown and looks something like this:

Code:
The system sends “server.mynewhostname.com”’s outgoing email from the “104.145.XXX.XX” IP address. The only PTR value for this IP address must be “server.mynewhostname.com”. This is the name that this server sends with SMTP’s “HELO” command to send “server.mynewhostname.com”’s outgoing email.

1 unexpected PTR value exists for this IP address:

server.myoldhostname.com
To fix this problem, replace all PTR records for “XX.XXX.145.104.in-addr.arpa” with the following record at “ns1.addr-arpa.io”, “ns2.addr-arpa.io”, “ns3.addr-arpa.io”, and “ns4.addr-arpa.io”:

Suggested “PTR” (PTR) Record PTR