http://rbl.schulte.org/
search to see if an IP is listed e.g.: 209.134.156.193

I decided to publish via DNS this list of IP addresses I don't want to get mail from. That way I could export it easily to my multiple SMTP servers via zone transfer or direct DNS lookup, and not have to maintain multiple access maps manually or via something like rsync. This RBL list is just one of many methods I use to manage incoming crud for my inbox and the inboxes of my users. My complete filtering solution includes things like: this RBL list other public RBL lists stricter requirements on remote SMTP RFC compliance sender domain validation realtime sender address verification greylisting keyword rejection on incoming email body keyword rejection on incoming email header spamassassin clamav procmail rules MUA filtering/spam identification ... and many other methods I generally add /24 or /16 catch all entries when repeated spam comes from a /24 or /16 and I don't foresee any legitimate email coming from these hosts. If you got a message telling you to come here because of a blocked email message, be aware that one of two possibilities exists: 1) you tried to send email to a host I manage from an email server that I have decided not to communicate with. 2) you tried to send email to a host which has decided to use my RBL list to block email. You have no choice but to resend the email from a different host, one which is not blocked. Anyone can use this RBL list like any of the other major lists ( cbl.abuseat.org, etc ) by adding this to your MTA's RBL config ( DNSBL, NOT RHSBL!): rbl.schulte.org With Postfix, for example, you can add this line where it's appropriate: reject_rbl_client rbl.schulte.org, Feel free to drop me a line if you want to communicate anything to me about this list: postmaster@schulte.org