Nigel wrote:
> This then begs the question that if you have a mailer which is unhappy
> with many recipients RCPT TO lines would be happy with muliple messages in
> a single TCP session.
Well, exim already has a setting that limits multiple messages down
the same pipe: batch_max. Combine this with a multiple RCPT limit and
fragile sites can be accommodated. (depending on how a multiple RCPT
limit is implemented and whether any required chunking increments the
batch counter).
> So if you handle this RCPT limit by chunking the message in several SMTP
> enverlopes but within a single TCP connection will the server be happy or
> die!!
Well, I don't know the innards of various MTAs, but I suspect some
could better handle several evelopes over one big one. Once the site
gets the data, transmission is complete. If a server dies in the
middle of trying to accept 10,000 RCPTs (for example, let's say it's a
smarthost accepting messages from a machine dedicated to large mailing
lists) no messages get sent at all since it never got the message
body. If instead the server is sent batches of 100 RCPTs per message
and it dies during the 50th one, then at least 4900 got out and the
remaining 5100 can be retried later when the server gets over its
indigestion.
--
Michelle Dick artemis@??? East Palo Alto, CA