Setting up the RBLDNSD Running Your Own RBL DNS Blacklist rbldnsd: Small Daemon for DNSBLs Does postfix cache RBL queries? Other Resources Is it possible to create an own DNS-Blacklist? How to create your own RBL DNS Blacklist to prevent
You can use any manual DNS tool, such as “host” or “dig”. You simply check if a DNS entry of type A exist in a respective DNS zone of the BlockList. For example for SpamHaus you check the *.zen.spamhaus.org zone.