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Re: ( /24) blocked by for SMTP

  • From: Omar Thameen
  • Date: Sat Sep 24 06:26:57 2005

On Tue, Sep 20, 2005 at 09:01:40AM +0530, Suresh Ramasubramanian wrote:
> On 20/09/05, Alan Spicer <> wrote:
> > 
> > I wonder if anyone with can tell me why this ip or /24
> > 
> > ( /24)
> > 
> > would be blocked from sending SMTP to customers.
> > 
> That's a large (and quite good) webhost called, which also
> hosts the Pittsburgh IX (
> Blocking is fine - happens.  Postmaster and other role accounts not
> replying at all to email that they're sent is just not a good thing to
> do.

This may give you an idea of what issue may be and the response
you're likely to encounter.

Back in June, we contacted Bellsouth postmaster regarding their
filtering of SMTP connections (i.e., so that connection attempts
hang until the timeout is reached), and received this reply from

	We will configure our settings for your company on our
	Filtering mechanism to 50 messages within a 5 minute window.
	We ask that you conform to this industry standards regarding
	submission of email to our mail server.

As you all know, 50 messages/5 minutes is abysmally low, particularly
for a mailing list hosting provider.  Our requests for higher
threshold and a pointer to the "industry standards" were summarily

If there's a Bellsouth contact with more of a clue on this list,
we'd be happy to meet any reasonable requirements you have for email

Omar Thameen

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