>>>>> "ESM" == Edward S Marshall <email@example.com> writes:
ESM> Machine "mj" hosts all of our mailing lists. Machine "shell" hosts all
ESM> of our shell users. We have a list on "mj" that consists of users
ESM> whose mailboxes reside on "shell". When the list is mailed, qmail
ESM> forks off its maximum number of processes to deliver individual copies
ESM> of this mail to "shell" for each user on the list, with the results
ESM> being very much like a DoS attack. Rather nasty.
This is what qmail does. This is the only behavior that qmail implements.
(I.e. make a separate connection for every address on a machine, even when
you could do it all in one connection.) According to the author of qmail,
there is no reason to do it any differently. Also recall that qmail sends
a tangibly different message to each recipient (because of the sender
hack), so it has no choice but to make separate connections. I suggest you
ask for a solution on the qmail mailing list; I do recall that the author
had come up with an SMTP replacement that perhaps two qmail-speaking hosts
could use instead.
ESM> Is there some way I can get qmail to handle this situation gracefully
ESM> (i.e. deliver ONE copy of the mail to "shell", and let it's mailer
ESM> (also qmail) deal with it appropriately)?
You could wedge something like TLB in there; TLB can move some addresses
off to another machine for delivery, which is essentially what you want
done. That isn't exactly what I call an easy solution, though. (TLB is a
package I have written to do this kind of thing. If you want to try it,
let me know.)
Jason L. Tibbitts III - firstname.lastname@example.org - 713/743-8684 - 221SR1
System Manager: University of Houston High Performance Computing Center
1994 PC800 "Kuroneko" DoD# 1723