Milters

This section covers the basics of how Milters works

Concepts

Email RBLs (real-time block-hole lists) Primer

• https://en.wikipedia.org/wiki/DNSBL

• https://en.wikipedia.org/wiki/Comparison_of_DNS_blacklists

• https://www.spamhaus.org/whitepapers/dnsbl_function/

• https://kb.mailchimp.com/delivery/spam-filters/how-blacklists-work

• https://www.pinpointe.com/blog/how-do-i-know-if-im-on-a-spam-blacklist

• https://rbltracker.com/blog/2015/07/what-are-rbls-and-how-do-they-work-part-1/

• https://blog.returnpath.com/blacklist-basics-the-top-email-blacklists-you-need-to-know-v2/

• https://techtalk.gfi.com/dns-blacklists-work/

• https://sendgrid.com/blog/email-blacklist/

Configuration

Check multiple global RBLs online

• http://multirbl.valli.org/lookup/

• http://mxtoolbox.com/

• http://www.dnsbl.info/

Troubleshooting & Log Parsing