what happens when you put a typo in a DNSBL server?

Wes Hardaker wjhns61 at hardakers.net
Tue Jan 16 16:36:03 UTC 2007

A number of ISPs use njabl.org as a DNS BL server.  However, starting
jan 2 a new domain exists "njalb.org" which is serving A records for
anything queried against it's DNS server.  (note the difference: njaBL
vs njaLB). Previous to this date a misconfigured ISP was just not
being protected by the BL.  Now, it's potentially dropping all mail
from anyone because of the typo.

# dig +short mail.merit.edu a

# dig +short

# dig +short

I know of at least one ISP that is likely dropping mail from
"In the bathtub of history the truth is harder to hold than the soap,
 and much more difficult to find."  -- Terry Pratchett

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