Sorry for didn't answer to your questions.
1. I'm facing a problem with the mail delivery to hotmail and gmail as they send and NDR as below:
Please note that it was working well without any problem.Quote:
Remote-MTA: dns; gmail-smtp-in.l.google.com Diagnostic-Code: smtp; 550-5.7.1 [18.104.22.168] The IP you're using to send mail is not authorized to 550-5.7.1 send email directly to our servers. Please use the SMTP relay at your 550-5.7.1 service provider instead. Learn more at 550 5.7.1 'The IP you're using to send email is not authorized...' - Gmail Help s8si24828960eeo.43
Anyway in order to avoid such as this problems, I tried to use the relay host and I applied the following settings:
Please note that there is A record if you read the DNS that I provided. Also the Cpanel is for me and I have root access tooQuote:
zmprov ms mail.domain.com zimbraMtaRelayHost mail.domain.com:25
echo mail.domain.com firstname.lastname@example.org:word456 > /opt/zimbra/conf/relay_password
postmap -q mail.server.com /opt/zimbra/conf/relay_password
postconf -e smtp_sasl_password_maps=hash:/opt/zimbra/conf/relay_password
postconf -e smtp_sasl_auth_enable=yes
postconf -e smtp_cname_overrides_servername=no
Any help would be appreciated...