Greylisting -- Was: Anti Spam

[Bart Silverstrim]

On Apr 28, 2007, at 5:25 AM, Ted Mittelstaedt wrote:

>
>
>> -----Original Message-----
>> From: Bart Silverstrim [mailto:bsilver at chrononomicon.com]
>> Sent: Friday, April 27, 2007 1:58 PM
>> To: Ted Mittelstaedt
>> Cc: Christopher Hilton; Grant Peel; Eric Crist;
>> freebsd-questions at freebsd.org
>> Subject: Re: Greylisting -- Was: Anti Spam
>>
>>
>>
>> On Apr 26, 2007, at 12:15 AM, Ted Mittelstaedt wrote:
>>
>>> There are legitimate technical reasons that someone may want their
>>> mail
>>> to not be greylisted.  For example, my cell phone's e-mail  
>>> address is
>>> in our monitoring scripts to page me in the event of a server  
>>> failure.
>>> I would be pretty pissed off if Sprint suddenly started
>>> greylisting.  It
>>> isn't just dumb-ass users making stupid political decisions to  
>>> reject
>>> it, although in your case it probably was.
>>
>> If it is a legitimate mail server, it would be promoted to the auto-
>> whitelist.  Not all mail is constantly greylisted by most intelligent
>> greylist systems.  Only the first few messages would be delayed,
>> until it is established as legitimate.
>>
>
> That won't work in my case since I generally only have a failure  
> that causes
> a problem which results in paging about once every 3 months or so.   
> By the
>  time the pages got through the
> greylist it would be at least an hour later after the system had gone
> down.  That isn't acceptable for a notification system.

What?  What do you mean, a failure that causes a problem which  
results in paging once every 3 months?

If your mail server tries to contact another mail server and it can't  
reach it, you're saying your mail server doesn't retry for an hour?

Even if it does take an hour, the fact that it retried the server on  
the other side doing the greylisting means it would be whitelisted  
after a couple mails.  If you're doing something SO critical that  
three or four mails delayed an hour, until you're establishes as a  
legit user, means life or death, you definitely should be doing  
something that backs up how you communicate with other sites, or  
you're not such a big fish that the other sites have already added  
you manually to their whitelists like AOL or Amazon mail servers  
would most likely be already, or other local ISPs that are known  
legit and I just don't feel like waiting for the system to add them  
automatically.