Actually, this isn't a bad idea, it just won't work with spamdyke.  As I 
understand it, you want to use a successful graylist entry as evidence 
that the sending server is legitimate.  For example, once a message from 
gmail.com has passed the graylist, there's no point in graylisting all 
of its future messages because obviously the server will retry and 
eventually pass the filter.  Always enforcing the graylist seems like a 
waste of time and resources.

Unfortunately, when spamdyke creates a graylist entry, it only looks at 
the sender's and recipient's email addresses.  It doesn't look at the 
sending server's name or IP address.  So, if a message is received from 
an aol.com mail server, from an aol.com email address, it will pass the 
graylist filter because AOL uses real mail servers that retry 
deliveries.  However, if a spambot on a cable modem sends a message from 
a different aol.com address, the graylist filter could stop it because 
the spambot won't retry the delivery.  Just because both messages appear 
to come from aol.com addresses is irrelevant.  The sending server is 
what's important.

Even if spamdyke checked the sending server's IP address, you still want 
graylisting to always take place.  Imagine a scenario where a business 
hosts their own email in-house, using an Exchange server behind a NAT 
firewall.  All connections to spamdyke, whether they are from the 
Exchange server or the virus-infected Windows workstations, will appear 
to come from the same IP address.  The Exchange server will always pass 
the graylist filter but the infected PCs won't.

A little background: spamdyke doesn't consider the sending server's IP 
address when graylisting because large mail hosts (e.g. GMail, AOL, 
Yahoo!) use multiple outbound SMTP servers.  When a user sends a 
message, server A will attempt to deliver it, get graylisted and put the 
message back in the queue.  Later, server B might retry the delivery and 
get graylisted again.  In that situation, a message could easily bounce 
before it passed graylisting.

-- Sam Clippinger

mrxxxmryyy wrote:
> Hello,
>
>   
>> You must be either hosting couple of user accounts only or
>> you had never spent a second reading your servers' logs.
>>     
>
> I'm not sure if it matters as far as my idea is concerned.
>
>   
>> Exampke below, just randomly-picked machine I have, todays log
>> (and I see thousands of this shit daily; replaced target,
>> legitimate domain with @x, but it does not really matter):
>>     
>
> I'm afraid it has nothing to do with the idea. To make it simple
> again: John and George have email accounts on my server. Jane (who
> has an email account on some server, not mine) sends an email to John.
> Since it is a legitimate email it is passed after graylisting.
>
> OK, and now the clue. There's next email from Jane. It is to George,
> and this is _the_only_ difference from email number 1 to John (so it
> would be passed if it was to John, however it is to George so it isn't
> passed because it's graylisted first).
>
> So, if email no. 1 has been passed and now Spamdyke remembers that
> every email from Jane (sender, IP, etc.) to John should be accepted
> for given time without graylisting it, why not make use of this and not
> to apply this rule for mail from Jane to George?
>
>   
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