The latest RBLmon news + some useful details on the RBLs we monitor.

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Since 28-Oct-2016, we’ve been receiving reports of inconsistent results from the following blacklists: – – – – Upon further investigation of these reports, we found out that the above RBLs had stopped responding to DNS queries and presently return null results when looking up their A DNS records. This can be confirmed...

Introducing IP Labels

The long-awaited feature allowing our customers to assign labels to their IP addresses is now available with all paid packages.   IP labels make it much easier for you to organize your IP addresses. This feature comes extremely handy to people who use our services to monitor a large number of IPs. Upon adding a...

Official Launch

We are very happy to announce the launch of RBLmon’s first official version. After almost a full year of hard work and beta testing, we’re now proud to present the result of our efforts. Maintenance and Official Launch

We are glad to announce that RBLmon is now ready for official launch. At 14:00 UTC tomorrow (Thursday, October 14th, 2010), all RBLmon systems will be taken offline for major software maintenance and upgrades. We expect several hours of downtime, during which we’ll be working on deploying the first official version of RBLmon.

The Composite Blocking List (CBL) is a very effective DNSBL that blocks email from exploited computers. The CBL takes its source data from very large spam traps and mail infrastructures, and only lists IP addresses that exhibit characteristics, which are specific to open proxies, viruses, stealth spamware applications loaded on a computer without the user’s...

“Fiveten” ( is a blacklist run by Carl Byington, who operates under the name of “510 Software Group.” This blacklist has been around for a decade now. It lists IP addresses for a large variety of reasons.

The SpamCop Blocking List (SCBL) lists IP addresses which have transmitted reported email to SpamCop users. SpamCop, service providers and individual users then use the SCBL to block and filter unwanted email. The SCBL is a fast and automatic list of sites sending reported mail, fueled by a number of sources, including automated reports and...

The only way you can get into SpamCannibal’s database is by sending spam or virus ladened email.

For years, this blacklist included IP addresses, which belong to ISPs that do not provide a method of contacting them. On September 13th, 2010, its creator Jeremy Bettis announced on his blog that the blacklist is no longer maintained and urges all ISPs to stop querying its DNS database.

Starting in September 2008, Barracuda Networks introduced the Barracuda Reputation Block List (BRBL – pronounced “bahr-bel”) as a free DNSBL of IP addresses known to send spam. Barracuda Networks fights spam and created the BRBL to help stop the spread of spam.
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