Status of rbl.cluecentral.net: DEAD

The rbl.cluecentral.net DNSBLs were created in 2001 or 2002 by Sabri Berisha. The goal: To list "all known assigned IPv4 address space, by originating AS and by country. [This is based on] a full routing view is extracted daily from a router in the default free zone. The AS->country mapping is done via the statistics which are being provided by the four RIR's, ARIN, APNIC, LACNIC and RIPE."

Today, the website warns that the rbl.cluecentral.net service is closed. Sabri notes that "[it has become] more and more difficult and time-consuming to maintain a trustworthy list I started to notice more and more errors. The list is no longer of the quality needed to use in a production environment."

The website warns that if DNS queries continue at a high level, the DNS servers are likely to be configured in a way that will cause 100% of inbound mail attempts to be rejected, for all mail servers still using rbl.cluecentral.net. This makes it imperative that you remove any rbl.cluecentral.net zones from your mail server configuration, as soon as possible.

Status of blackholes.us: DEAD

Created by Matthew Evans in 2002, the goal of the blackholes.us site was "to create (yet more) DNS blocklists of spammers, spam supporting ISPs, spamware hosts, dialup networks, and other notorious email abusers originating in the United States." Matthew published many different DNSBL zones, listing various countries, ISPs, netblocks, etc.

Status of vox.schpider.com: DEAD

Scott Glassbrook writes: "I ran a dnsbl, vox.schpider.com many many years ago. I stopped the DNSBL back in June of 2006, and shut down the server it was running on. 

"Since that time, all queries to vox.schpider.com have timed out. I made an attempt to bring the domain name back up in 2008, only to find that people are still trying to query the domain name. [...] Because of that, I see no other option than to start returning positives for *any* query issued to vox.schpider.com, beginning 10/16/2009. If you happen to be trying to use a dead DNSBL, please update your mail server configuration."

Scott indicates that random mail administrators are still "pounding the hell" out of his DNSBL hundreds fo times per second, all day and all night, ever day. Not cool.

If you're still querying this DNSBL, it's important that you immediately remove it from your mail server configuration. As of October 16th, use of this DNSBL will result in you rejecting 100% of your inbound email.