Re: slow email validation problems

On Wed, 14 Sep 2005 21:20:41 +0200, Bogdan Tomchuk said:

> When your system decide to reject message as it consider it as SPAM what 
> would have to do remote system? Bah... exactly the same as that what you 
> refusing to do: it will generate bounce.
Almost all successful moral systems have, at their base, the concept that
"I will avoid doing Bad Things, even if others are doing them, just because
not doing them is The Right Thing To Do".

> I still have a lot of trouble to get why lot of peoples on this list try, in 
> some 
> way, to move there decision responsibility on remote system.
RFC2821 says:

6.1 Reliable Delivery and Replies by Email

   When the receiver-SMTP accepts a piece of mail (by sending a "250 OK"
   message in response to DATA), it is accepting responsibility for
   delivering or relaying the message.  It must take this responsibility
   seriously.  It MUST NOT lose the message for frivolous reasons, such
   as because the host later crashes or because of a predictable
   resource shortage.

OK?  Re-read that until you understand - sending a '250 OK' is to be taken
*seriously*, to the point where losing a message because the system crashes
is considered a "frivolous" excuse.

As a result, it's in my interest to do *anything* I can to avoid sending that
'250 OK' unless I'm very confident that I can deal with it - after all, I know
that while I'm busy being indecisive, it's safely queued on the sending system
that issued a '250 OK' before trying to forward it to me. ;)

And now putting on my BOFH hat:

If you accept it, and it's spam, it means there's a spam source in the
sender site.  If you then violate the RFCs and silently discard it, it
won't get fixed.  On the other hand, if you refuse to '250 OK' it, it will
eventually get bounced by the sending system - and probably double-bounce
because the spam injector used a bogon MAIL FROM:.  And maybe, just maybe,
all those double bounces will hit the mail admin on the head and clue him
in that he has a spam problem that needs fixing....

Remember - a double bounce drops into a human's lap in the hopes that they
will be able to fix the issue.  So you should go out of your way to make
sure that when it double bounces, it lands in somebody else's lap if it's
somebody else's problem....

pgpFNZlLBUjnO.pgp
Description: PGP signature