question on ptr rr

Sun Feb 8 16:50:44 UTC 2004

> Now, from your logs, just how much legitimate mail do you get that comes 
> from an IP without PTR RR, and how much is that expressed as a 
> percentage of legitimate incoming mail to your lists?  How much is that 
> as a percentage of spam inbound to your list [to be fair, let's make it 
> "spam that would not have been stopped by your other filters]?

well, it's gonna be hard to quantify what spam filters, bounces,
... rejected, and especially to associate them with smtp connections.

but here are some simple data.

yesterday, a saturday (gmt clock)

  48293   total incoming smtp connections
   6226   from ip addresses for which no ptr exists (12.89%)

  12416   unique ip addresses which connected to server
   3112   unique ip addresses for which no ptr exists (25.06%)

some inferences might be drawn, but i am hesitant to do so.

what numbers do YOU have for your server(s)?

randy