Can someone from SORBS contact me offlist?

James Hess mysidia at
Sat Jul 11 19:35:41 UTC 2009

I wouldn't condone usage of SORBS' lists,  because they sometimes use
robots to automatically list  things that have little rational basis
for being listed, which causes problems.   But it may be hard to
convince your mail recipients to avoid the same.

Commonly,  providers may  give un-assigned subnets generic PTR records
like ""  over their IP space. SORBS
automatically lists these in the DUHL.   And does not automatically
remove them later, when the reverse zone is populated with final

Legitimate mailservers  that do not originate spam routinely appear in
the DUHL  (and get blocked by users of the list).

> How would you like it if a non-customer came to you demanding resolution to
> a problem with a free service you provide?  Would you drop everything, and
> give that non-customer the same service you give a paying customer?

That depends on the service. The  DNS root servers provide a free
service to internet users who aren't customers.  If those servers all
started directing users'   .COM,  lookups to an incorrect TLD server,
so nothing resolved,  people would be upset if $root_server_operator
told them to wait 2 weeks.

People who consume a blacklist might get that service for free, but
they only do it on reliance that the blacklist follows the policies
that the maintainer had published for their blacklist.

In other words, that they provide what they say they are providing,
and not something different.  The expectation of timeliness arises,
because internet applications, services like the web and e-mail are
time-critical,  no ability to send  e-mail may mean lost revenue.

An improper blacklist entry (or even a proper one) does direct,
immediate, and serious damage to the party listed,   and this injury
is caused directly by the actions of the blacklist provider
maintaining the list entry.

I would suggest blacklist services have a moral duty to take
reasonable measures  to ensure they are not  inflicting  excessive,
easily avoidable damage on innocent third parties,  with stale or
erroneous  entries in their lists.

If people believed a blacklist did not  take reasonable measures to
correct errors quickly, then it would be understandable that their
reputation suffers.


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