Getting a new server

Ted Mittelstaedt tedm at toybox.placo.com
Fri Feb 3 03:13:44 PST 2006


Well the worst is verizon.net's servers.  Verizon runs a home-grown
callback verifier.  You send them an e-mail and during the SMTP
acceptance phase they attempt a mail-from from a separate IP subnet
( 206.46.252.0/24 ) and if that gets delayed, they don't accept
the mail.  (if it works they abort the smtp phase of the verifier,
and complete the acceptance of the message they send to you.  The
problem is the verifier comes from a random IP number in that
range.  You could spend all day long resending to them before getting
lucky and having their verifier use the same IP number it used
before.

We also found a few idiots running obviously hacked mailservers.
For example the local newspaper here, the Oregonian, if you
issue an error 4xx to their server, they will abort and return
to sender in violation of the RFCs.  Integra telecom is another
one that does something similar to that, they ignore error 4xx's
and assume your site isn't acceptimg mail from them.

We have also had trouble with yahoo, not all the yahoo IP subnets
that send mail are listed in the greylist exception list.  But I
don't know yet if we have stomped that, because we are still having
trouble with mail from yahoo groups, it's all coming in duplicated
twice.

Ted

>-----Original Message-----
>From: Alex Zbyslaw [mailto:xfb52 at dial.pipex.com]
>Sent: Thursday, February 02, 2006 3:58 AM
>To: Ted Mittelstaedt
>Cc: freebsd-questions at freebsd.org
>Subject: Re: Getting a new server
>
>
>Ted Mittelstaedt wrote:
>
>>[...] But, seriously think about chucking
>>all that and just run greylist-milter. [...]
>>
>>There's a few IP numbers and mailservers that need to be defined
>>in the exclusion list for greylist milter that aren't in the stock
>>exclusion list, but other than that, it is the best antispam tool I've
>>used in years.
>>
>>
>>
>Can you elaborate a little?  I.e. what IP's and mailservers, and why?
>Thanks,
>
>--Alex
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Free Edition.
>Version: 7.1.375 / Virus Database: 267.15.0/248 - Release Date: 2/1/2006
>



More information about the freebsd-questions mailing list