May 16, 2019
cPanel Access Level
Root Administrator
Hi, All

I need help with the configuration of a reverse DNS, I have it configured as they indicate me in the documentation of cPanel / WHM but I still can not validate the registration.

I have an instance hosted on AWS and a registered domain name.

Centos 7.6 and cPanel v78.0.23

Email Deliverability:

the other record that I added was validated correctly (DKIM and SPF), I only have a problem with the PTR record.


I did the following steps,

dns functions: add a zone with the domain name and the address ip.

10x.1x0.1x2.3x.in-addr.arpa. > 3x.1x2.1x0.10x

Then edit the zone, adding a ptr record with the name and value.

10x.1x0.1x2.3x.in-addr.arpa. > server.domain.net.


I am new implementing cPanel / WHM, sorry if I did some stupidity.

I do not know, if the problem I have with adding emails is due to this, I will leave some screenshots.

When I try to add an outlook email, only incoming mail is connected but not outgoing mail.
error_1.PNG error_2.PNG

look for another alternative and try to configure it with another mail application (Thunderbird) and I could configure the mail.

works correctly.

but my goal is to achieve it with Outlook.

I'm not an expert in the area, I'm just trying to find a solution and thanks for your contributions.

My English is not very good, I hope you understand me.

Best Regards.



Staff member
Apr 11, 2011
Hello @dxgrake,

1. First, make sure 1:1 NAT is is configured on your server per the instructions on the document below:

1:1 NAT - Version 80 Documentation - cPanel Documentation

2. Then, browse to WHM >> Edit DNS Zone and select the DNS zone for your server's hostname (or select the DNS Zone for the parent domain name associated with your hostname (e.g. domain.tld instead of hostname.domain.tld if a separate zone for "hostname.domain.tld" does not exist). When viewing the zone, ensure an "A record" is setup for the hostname pointing to the server's public IP address.

3. Remove any custom RDNS DNS entries or RDNS zone files you created, as AWS requires you to request the RDNS record directly through them.

4. Request the RDNS record using Amazon's instructions:

Configurable Reverse DNS for Amazon EC2’s Elastic IP Addresses | Amazon Web Services

Let me know if this helps.

Thank you.