This article explains how to setup VisNetic MailServer to perform reverse lookups on inbound mail. This option may help reduce the amount of SPAM received.
From the VisNetic MailServer console:
NOTE: This option Checks to see if the senders domain has a Mail Exchange DNS Record. VisNetic MailServer will perform a MX lookup and reject the mail if no MX record exists. If you have incorrectly configured your DNS server this can cause real harm.
- Select Delivery
- Click to enable the option Reject if senders IP has no rDNS. If no PTR records are found or the PTR records do not match the sending address, VisNetic MailServer will reject the email.
- Click Apply
- You can also click and enable the option Reject if originators domain has no MX record.