On Sun, 1 Jun 2025, John Curran wrote:
Out of curiosity, is there a reasonably clear document somewhere that describes how such network-level block lists should be operated from the view of network operators; i.e., a “best practice” statement ...
Sort of. See RFC 6471, Overview of Best Email DNS-Based List (DNSBL) Operational Practices. Running a useful blocklist is very hard. Everyone who's listed insists that it's a mistake. Sometimes they have odd ideas of their responsibility ("we have no control over the customer, we just take their money and route their packets".) Sometimes they are sure they are special so the regular rules don't apply. Sometimes they are confused. Often they just lie. Occasionally, there really is a mistake but recoginizing it in the noise is not easy. Regards, John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly