Arrogant RBL list maintainers

Sean Donelan sean at
Wed Dec 16 09:55:16 CST 2009

On Wed, 16 Dec 2009, James Hess wrote:
> On Tue, Dec 15, 2009 at 11:30 PM, Adam Armstrong <lists at> wrote:
>> personally, i'd recommend not being a dick and setting valid *meaningful*
>> reverse dns for things relaying mail.
> Many sites don't use names that will necessarily be meaningful to an outsider.
> Sometimes the non-meaningful name is the actual hostname and the
> _only_ name that machine is known by,  even if the name appears
> "generic" or contains an IP.   Host naming is a matter of local
> network policy, and the RFCs that pertain to hostnames specify syntax
> requirements only.

You can implement your local network policies to use mail server hostnames 
which match "generic" looking strings, and other operators can implemenent 
their local network policies to refuse mail from hosts which match 
"generic" looking hostname strings.  In the battle of local network 
policies, you will always lose because there are always more other 
networks.  If you want to interoperate with other operator's networks, you 
will probably need to follow more than just your local network policies.

Folks have said what the problem is, and how to fix it.  If the original 
poster wants to stand on principles, he will continue to have problems 
getting other networks to accept connections from his mail servers. 
On the other hand, if he wants to fix this mail acceptance problem, he 
now knows what he needs to do.

The great thing about RFCs is anyone can write one.  The bad thing about 
RFCs is anyone can write one.

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