I installed Zimbra email server in my infrastructure which has a firewall and gateway installed on another server which has public IP and mail.example.com is pointing it to. We set up port number of the email server to xxxx and access email server using url mail.example.com:xxxx. Now when I tried sending email from an account on this email server to gmail id, it says undelivered mail status as below:
550-Please turn on SMTP Authentication in your mail client, or login to the
550-IMAP/POP3 server before sending your message.
<rDNS Addr>:35215 is not permitted to relay through this 550 server without authentication.
I seen https://productforums.google.com/for...ps/Fm9KK8qvi1E this post but I cannot add TXT record in DNS as advance domain control panel don't have such option. It has A record and CNAME record options only.
I neither can send email from gmail to email on server and don't even get any delivery status email or bounce email. What am I missing.
Steps to Reproduce:
1) Install two servers in a network A and B. Configure gateway and firewall on one of server (A) and allow incoming traffic and outgoing traffic from this server.
2) Install Zimbra email server on another server (B) and made it to listen https on port xxxx.
3) Now configure DNS to point its MX record at server (A).
4) Test (B) server to send and receive emails.