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I have a CentOS 7 droplet that currently hosts 4 domains running Virtualmin/Webmin.
The dropled is named example.com (which is one of the 4 domains). PTR record is updated correctly with the droplet IP.
BIND DNS Server module is disabled, as I am using the “Networking > Domains” panel provided by DO. Per each of my domains, I have configured DNS as follows:
A @ *droplet ip*
A mail *droplet ip*
CNAME www domain.com.
CNAME * domain.com.
MX 5 mail.domain.com.
TXT @ "v=spf1 a mx a:domain.com ip4:*droplet ip* ?all"
NS ns1.digitalocean.com.
NS ns2.digitalocean.com.
NS ns3.digitalocean.com.
Here are my /etc/hostname
server.example.com
And /etc/hosts
▽
127.0.0.1 server.example.com server
127.0.0.1 localhost.localdomain localhost
127.0.0.1 localhost4.localdomain4 localhost4
::1 server.example.com server
::1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6
*droplet ip* server.example.com
And /etc/resolv.conf
# Generated by NetworkManager
search example.com
nameserver 127.0.0.1
nameserver 8.8.8.8
nameserver 8.8.4.4
Finally, I have setup a forward from postmaster@domain.com to my gmail account.
Here the issue comes: if I send a test email from my outlook account to postmaster@domain.com I expect it to get it delivered to my gmail account. However, this is what I get back:
This is the mail system at host server.localdomain.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to postmaster.
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
<myemail@gmail.com> (expanded from <postmaster@domain.com>): host
gmail-smtp-in.l.google.com[74.125.133.27] said: 550-5.7.1 [*droplet ip*]
The IP address sending this message does not have a PTR 550-5.7.1 record
setup. As a policy, Gmail does not accept messages from IPs 550-5.7.1 with
missing PTR records. Please visit 550-5.7.1
https://support.google.com/mail/answer/81126#authentication for more 550
5.7.1 information. r7si49844073wmg.47 - gsmtp (in reply to end of DATA
command)
What am I doing wrong?
3630316526124b4190e628cd69be1e
6a2e133a62fe4859920f9233303d8c
c6fa584e45c14c21ae44129dfe5743
Maria Smith
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bitandmap
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5f21ced7a9dd4fe7af83c7412c563f
David Sen