Several organizations publish e-mail (or any other service) abuse lists (aka RBL, abbreviation for "Real-time Blackhole List") using DNS
(Domain Names System) protocol, concepts and software (DNSBL black lists
). This script inquires those lists to determine if a particular host is present. Inclusion of a particular list in this utility should not be construed as an endorsement by the script author. I use some of these lists for email filtering. I believe some of these lists are evil. You should visit their web pages, read their policies, and decide for yourself. This free dnsstuff tool supports both traditional DNSBL (IP address
) and RHSBL (domain name).