[Esd-l] smashing unknowns

Kenneth Porter shiva at well.com
Tue Jul 30 20:16:00 PDT 2002

On Tue, 2002-07-30 at 09:59, Simon Matthews wrote:
> Scott,
> I don't think this is a case of poorly configured MTAs, rather it is simply 
> that their IP address does not resolve to a name (no PTR record for the IP 
> address). This can only be fixed by the owner of the IP address range.
> Like many other companies, we run our own mail server -- we don't relay via 
> our ISP. Unfortunately, neither of our IP address ranges have working 
> reverse lookups, so most people will see "unknown" in the headers of emails 
> that we send.

This issue comes up occasionally on the DNS policy mailing lists, and I
think most people have just come to accept that good, working reverse
DNS is hard because it's hard to get many ISP's to cooperate. If you
don't pay big bucks for a tier 1 ISP, well, you get what you pay for.

I'm fortunate in that my UUNET and PacBell commercial connections both
delegate my reverse to me, so I have full control over those names.

The real trick is knowing what to ask for and, even more, knowing who to
ask to get the delegation done. It took me several days a couple years
back to find the right PacBell information, as it wasn't on their
support website at the time.

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