[65659] in North American Network Operators' Group
Re: AOL rejecting mail from IP's w/o reverse DNS ?
daemon@ATHENA.MIT.EDU (Suresh Ramasubramanian)
Thu Dec 4 15:02:13 2003
Date: Thu, 04 Dec 2003 15:00:48 -0500
From: Suresh Ramasubramanian <suresh@outblaze.com>
To: Chris Lewis <clewis@nortelnetworks.com>
Cc: nanog@nanog.org
In-Reply-To: <3FCF89EC.2070609@americasm01.nt.com>
Errors-To: owner-nanog-outgoing@merit.edu
Chris Lewis writes on 12/4/2003 2:24 PM:
> As I understand it, they blacklist if an IP with no rDNS generates "some
> threshold of" complaints. Not just "no rDNS" by itself.
That is a good way to go.
> A simple "no rDNS" rule causes too much trouble with our overseas
> customers. I'm sure AOL discarded that idea for the same reason.
Yup. The model can be extended to "if no rDNS, and if spamtrap hits or
other spammish behavior noted from more than X IPs per /24, then block
the /24".
srs
--
srs (postmaster|suresh)@outblaze.com // gpg : EDEDEFB9
manager, outblaze.com security and antispam operations
