[Mimedefang] Spam to inactive accounts

listuser at neo.pittstate.edu listuser at neo.pittstate.edu
Wed Oct 16 23:21:02 EDT 2002


It definitely should.  Otherwise it would test as an open relay, face
value anyways.  This is the problem with Novell servers IIRC.  They fully
accept the message, then check to see if the user actually exists, and
finally send a bounce under separate cover if the user doesn't exist.  The
only real way to test if it's an open relay is to send yourself a test
message through that server and see if it actually gets back to you.
There's a fix for this in the Novell support area though.

Back on track, IIRC Sendmail does reject the message with a User Unknown
during the SMTP transaction.  delay_checks should affect this either since
delay_checks simply delays the rejection (say for example you've told
Sendmail to block that domain or you DNSBl matched the sending IP) until
after the recipient list has been received.  I'm pretty sure this is how
it works.  This is what happens on my boxes at least.  I suppose it's
posible that Sendmail could be configured to accept the mail regardless of
the recipient and let the LDA determine if the user exists.  This is
rather wasteful IMHO.

Justin


On Wed, 16 Oct 2002, Jeff Grossman wrote:

> Doesn't Sendmail tell the sending server that the account doesn't exist
> during the SMTP Transaction stage?  That would mean the message never
> really makes it to your machine.  So, there should not be a bounce
> message.  The bounce message should be created by the machine sending
> you the invalid message.
> 
> Jeff




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