Reject vs. bounce

[John Rudd]

Tim Boyer wrote:
> Apologies if this has been discussed ad infinitum before.  I've been running a
> mailserver since 1996, but just heard about MailScanner Saturday, thanks to
> Steve Swaney's excellent talk at the Ohio LinuxFest.
> 
> I've been using DNSBLs and a private blocklist with SpamAssassin, and ClamAV as
> milters, so when I reject an email it's rejected, not bounced back to the
> (99.999% bogus) 'From" address.  
> 
> I've heard and read that MailScanner has a 'bounce' option.  Is this what I
> think it is - a bounce back to the 'From'?  Or is it a reject before the
> connection's been dropped and the email accepted?
> 

It is a bounce back to the "From" address, not a rejection during the 
connection.  Mailscanner doesn't run during the SMTP session, therefore 
it can't do SMTP rejections nor SMTP tempfails.