[103677] in North American Network Operators' Group
Re: Problems sending mail to yahoo?
daemon@ATHENA.MIT.EDU (Mike Lewinski)
Thu Apr 10 16:21:59 2008
Date: Thu, 10 Apr 2008 13:43:15 -0600
From: Mike Lewinski <mike@rockynet.com>
To: nanog@nanog.org
In-Reply-To: <!&!AAAAAAAAAAAuAAAAAAAAAKTyXRN5/+lGvU59a+P7CFMBAN6gY+ZG84BMpVQcAbDh1IQAAAATbSgAABAAAAAWhN7qvNGSQpCyUI3fjJnUAQAAAAA=@iname.com>
Errors-To: owner-nanog@merit.edu
Frank Bulk wrote:
> Q> Does Yahoo! use "greylisting" to reject messages?
>
> A> No.
> The most commonly understood form of "greylisting" is where an
> SMTP server will reject every message the first time it is
> attempted, and then accept it if the sending server retries
> later. The theory is that spammers won't retry messages, while
> legitimate senders will.
>
> Yahoo! does not utilize this method.
>
> http://help.yahoo.com/l/us/yahoo/mail/postmaster/postmaster-05.html
Whatever they call it is immaterial. The end result to our system is
indistinguishable from real greylisting. Perhaps there's a tiny fraction
that aren't ever deferred, but in general I find the majority of our
queue is destined to @yahoo.com addresses.
I think I'll followup on the other posters ideas of:
1) Implementing a separate outbound gateway just for yahoo.com
2) Advising users to switch to gmail.
