Emails getting rejected from Gmail on Virtualmin/Webmin and CentOS
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
▽ 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
# Generated by NetworkManager search example.com nameserver 127.0.0.1 nameserver 18.104.22.168 nameserver 22.214.171.124
Finally, I have setup a forward from email@example.com to my gmail account.
Here the issue comes: if I send a test email from my outlook account to firstname.lastname@example.org 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 <email@example.com> (expanded from <firstname.lastname@example.org>): host gmail-smtp-in.l.google.com[126.96.36.199] 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?