All about DNSBLs, aka blocklists/blacklists // Since 2001 // Published by Al Iverson
Thanks for visiting! Remember that nowadays, (most) blocklists don't really govern deliverability and inbox placement. Want to learn more about email marketing best practices, email technology, and deliverability troubleshooting? Then you'll want to check out my other site, Spam Resource. |
Status of blackholes.intersil.net: DEAD
Status of blacklist.spambag.org: DEAD
Spambag, created and run by Sam Varshavchik, developer of the Courier mail server, has been operating this list since at least November, 2001.
The list had the following listing criteria: "[Spambag is my] personal list of networks who I block from sending me mail or accessing my web servers, because I believe the networks actively or passively allow abusive or antisocial behavior. Examples of what I consider abusive or antisocial behavior are: spamming, mailbombing, mail server dictionary attacks, and web page E-mail address harvesting."
I last noted a hit against this DNSBL on May 26th, at 1:34 am US central time. Note that I was not a user of this list; I simply measure its effectiveness and status, like I do for many other lists.
This post to news.admin.net-abuse.email explains that Sam Varshavchik shut the list down, and that he felt his efforts had not been as productive as he would've liked them to be.
I would recommend removing blacklist.spambag.org from your list of DNSBLs to check, as it is no longer in operation.
Spamcop BL: Take Another Look (It’s Accurate!)
If you know me, you know that in the past, I’ve made no secret of my disdain for the Spamcop DNSBL, aka the SCBL.
I was trying to do the right thing. I was implementing what Spamcop (and other anti-spam groups) want: confirmed opt-in/double opt-in. Yet Spamcop was listing the servers and subsequent mailings regardless. It made me really frustrated, and I was very disappointed. See, it’s not really fighting spam. It’s just blocking mail you don’t like, or don’t care about. While perfectly allowed, I am of the opinion that it’s lame to do so under the banner of “fighting the good fight” to stop spam. I’ve shared my thoughts on this topic in just about every available forum—websites, blogs, discussion lists. I know I’ve personally guided many sysadmins away from using the SCBL in the past, because it was easily, demonstrably, listing things that were obviously not spam.
In February 2007, I found that Microsoft was using the SCBL to filter/reject inbound corporate email. (Note that I said corporate email—mail sent to users at micrsoft.com, not users of MSN or Hotmail. I don’t know whether or not SCBL data is used in MSN Hotmail delivery determination, but from what I’ve observed, it doesn’t seem to be.) This started me off on another rant on how ill-advised I felt this was, based on my prior experiences with Spamcop. Some kindly folks (and some less kindly) suggested that I needed to revisit my opinion of the Spamcop blocking list, because things have changed.
DNSBL | Spam hits | Acc % | Ham hits | Failure Rate |
Spamcop SCBL | 156194 | 49.37% | 0 | 0.00% |
Spamhaus ZEN | 255521 | 80.77% | 5 | 0.10% |
Spamcop+ZEN | 267795 | 84.65% | 5 | 0.10% |
| | | | |
Range: | ~ 74 days | | | |
Total Spam | 316348 | | | |
Total Ham | 4999 | | | |
As you can see, Spamcop helps you attack nearly 50% of spam received, while affecting no legitimate senders. Very few lists do better. Spamhaus ZEN (which combines multiple lists) does better, but will occasionally have a false positive, based on some reputational issue perceived with a given sender.
Spamcop Roundup http://www.dnsbl.com/2007/03/spamcop-roundup.html Spamcop BL: A blocklist with a hair trigger http://www.dnsbl.com/2007/02/spamcop-bl-list-with-hair-trigger.html Microsoft using Spamcop BL http://www.spamresource.com/2007/02/microsoft-using-spamcop-and-spamhaus.html My Problems with Spamcop http://www.spamresource.com/2003/03/problems-with-spamcop.html
Status of relays.orbs.org: Shut down, legal troubles in 2001
People keep asking me about the situation regarding ORBS and its eventual downfall. It happened so long ago, that I don't feel that it would be appropriate to try to fill people in from memory alone. Instead, here's links to a lot of the articles I've found regarding Alan Brown and ORBS. If you have any others, drop me a line and I'll add them to this page.
- Wikipedia's page on ORBS.
- Thread from the newsgroup nz.comp that discusses the shutdown and contains opinions regarding ORBS' listing policies.
- Here's an overview of legal action against Alan Brown, I believe around the same times as ORBS was imploding. Apparently he was sued for defamation over this newsgroup post, and lost. (More commentary on that here, from someone else involved, writing about it a couple of years after the fact.)
- This Register article talks about the legal action against Alan Brown and ORBS regarding Alan's listing of Xtra and Actrix. Courts found that they were falsely listed on the ORBS blocking list.
- An Actrix rep points out that the reason they were listed is due to getting sucked into the disagreement between Alan Brown and Domainz Followups from others indicate that the Actrix IP address was listed as an open relay input. According to Actrix, it was not an open relay.
- Some newsgroup commentary regarding the defamation suit and ORBS listing policies.
- Tom Betz posts Alan Brown's statement to SPAM-L encouraging the blocking of Telecom NZ and indicating that he's no longer in New Zealand.
- Here's an interesting article about ORBS and the controversy surrounding its practices, from Salon.com.
Status of rbl.cluecentral.net: ALIVE
The DNSBL “rbl.cluecentral.net” has been revived. Its maintainer, Sabri Berisha, had previously shut it down in November 2005.
This list aims to allow you to allow or block mail from specific countries, or from certain routers (by AS number).
For example, if you wish to block all mail from the
Note that while these lists may be used to block spam, they're not exactly spam-blocking lists. Rejecting all mail from China simply means that you're going to reject all mail from China, spam or non-spam. It's up to you to determine whether or not this is an acceptable compromise. I assume, like with users of korea.services.net, administrators who choose to use this list are fed up with spam from a certain country's servers, and receive little enough legitimate mail from a country that the risk of false positives is considered acceptable.