W dniu 2009-04-15 04:21, Rod Whitworth pisze:
--Original Message Text---
*From:* Pawe+‚ Le+›niak
*Date:* Tue, 14 Apr 2009 14:50:57 +0200
8>< snip---------
I don't like top-posting but......
Due to your message formatting it is not possible for someone to
easily see who said what in your reply. So simply for the benefit of
others who may have had a passing interest, I'll make closing comments.
Talking about formatting - try to use somewhat newer client, with good
message formatting. I have no problem to follow the thread.
All talk about RFCs in your message is irrelevant because messages
from the null sender addressed to a fictitious recipient will NEVER be
delivered anyway. RFC3834 is NOT a standard BTW, and we should hope it
never is as it contemplates things like sending virus notifications.
Echhhk!
Have a look at http://www.postfix.org/bounce.8.html. Specially part
STANDARDS. So it looks like RFC3834 IS a standard indeed.
So we trapit <> to invalid addresses and reading the logs shows that
the probability of those messages being bounces from servers
configured by amateurs is something like .999977.
You can do whatever you want. But do not enforce others to break RFCs.
Talking about amateurs ... I do agree with that. But you won't do any
good by messing. It would give better effect if you'd report them to
some RBLs. If they get blacklisted with zen, they'll have to think over
their configuration.
You have no idea how little load this places on our firewall. It is
not even measurable when there is a spambot storm in progress. It does
not consume any Postfix resources. It also seems that the tarpitting
we do on other spammy senders is noticed by some of them as the number
of trapped IPs at any instant is now about a quarter of what it was a
year ago.
We don't slow down our network by tarpitting. The sender gets 1 char/
4 seconds and typically gives up after about 1500 seconds with the
settings I use.
I did not mean your network. If there were many sites like your, it
would be simple to fill up network attacked by few spambots. Have you
ever thought that some sites share network connection?
Of course it gives up after first limit (client or server side) occurs.
So it can be 300 seconds when sender stops (5 minutes limit is proposed
in standard), or any other limit configured at the other side.
For more info see
http://www.openbsd.org/cgi-bin/man.cgi?query=spamd&apropos=0&sektion=0&manpath=OpenBSD+Current&arch=i386&format=html
And that's all folks! Back to lurking for me.
One more thing... you forgot to comment the part about what kind of
emails can be sent with null sender address.
- SAV
- Auto-replies- - (...)Since in most cases it is not appropriate to
respond to
an automatic response, and the responder is not interested in
delivery status messages, a MAIL FROM address of <> MAY be used for
this purpose.(...)- RFC3834
- Any type of automated notifications (...)In some types of
reporting messages for which a reply is likely to cause a mail loop
(for example, mail delivery and nondelivery notifications), the
reverse-path may be null (see section 3.7).(...)- RFC2821
Still - you can do whatever you want.
Pawel Lesniak
