Zimbra Enable PTR/Reverse DNS lookup Incomming Email
A reverse DNS lookup or reverse DNS resolution (rDNS) is the querying of the Domain Name System (DNS) to determine the domain name associated with an IP address – the reverse of the usual "forward" DNS lookup of an IP address from a domain name. Zimbra tips, How to Enable PTR/Reverse DNS lookup Incomming Email. More information from Wikipedia . Step 1: Enable zimbraMtaRestriction as command below su - zimbra zmprov mcf +zimbraMtaRestriction "reject_unknown_client_hostname" Step 2: zimbra postfix reload postfix reload Conclusion Thought the article, you can use "Zimbra Enable PTR/Reverse DNS lookup Incomming Email" as above . I hope will this your helpful.