[Mimedefang] OT: DNS sanity check

[Les Mikesell]

John Rudd wrote:
> Les Mikesell wrote:
> 
>> Please show me where it says you _MUST_ accept from IP's that do have
>> reverse DNS configured to match the A record before I go looking for an
>> equivalent mandate for the case where they don't.   I don't believe
>> either exists, and any decisions based on sender DNS lookups are
>> entirely arbitrary, not standards-based.
>>
> 
> 
> a) Correct, you are not required to accept any message.  You can always
> reject them, evne if they have correct reverse DNS.  That doesn't
> contradict anything I've asserted.  If anything, it agrees with what I'm
> asserting: unless you are directed that you MUST, then you don't to.
> 
> 
> b) They are not arbitrary, they are based upon best practices as stated
> in the RFC I put into my first message in this thread.  It clearly
> states that if you should have matching PTR and A records, and that if
> you don't you should expect to have people refuse to deal with you.
> 
> 
> My position on this is supported by a best practices RFC.  Yours isn't
> even supported by the RFC sections you've quoted.

You can support a claim that it is a recommended best practice to
provide matching A and ptr records in your DNS.  It is beyond stretching
things to claim that refusing email is a best practice.

-- 
   Les Mikesell
    lesmikesell at gmail.com