Mark, thanks for the very detailed info below. I am still stuck on this. This sendmail server is setup to relay the mail to smarthost. When I inject a test mail on port 25 with RCPT and FROM to be a made up junk domain, the email is still delivered *immediately* to the smarthost, there is no resolver issues.
If sendmail was really doing DNS lookups, I would think it would be stuck locally or throw a bounce/error right away. It just seems like it's running serially, and not dequeueing multiple messages to the smarthost at a time. Anil PS: Putting a local DNS cacheing server is a possibility, but not yet. On Feb 1, 2012, at 10:56 PM, Mark Sapiro wrote: > Anil Jangity wrote: > >> Does mailman actually (if it works) send to 15 recipients at a time - per >> SMTP session? > > > Mailman's use of the term session is not consistent with the RFCs. What > Mailman calls SMTP_MAX_SESSIONS_PER_CONNECTION is actually in RFC 821, > 2821, 5321 terms, max transactions per session. I.e. one session is > one connection from HELO/EHLO to QUIT and one transaction is one MAIL > FROM and everything that follows up to the next MAIL FROM. > > Unless you have some specific MTA reason for setting > SMTP_MAX_SESSIONS_PER_CONNECTION, you should leave it at the default > value of 0 meaning unlimited. > > If a message is personalized or VERPd, SMTP_MAX_RCPTS is ignored > because you can't send a personalized or VERPd message to more than > one recipient. Otherwize, SMTP_MAX_RCPTS is the maximum number of RCPT > TO recipients in one MAIL FROM transaction. > > Note that 6000 users per 35 minutes is less than 3 per second. This is > extremely slow. I typically see 30 to over 60 recipients per second on > a rather ordinary production server with full VERP. > > See my reply to your original post in this thread at > <http://mail.python.org/pipermail/mailman-users/2012-January/072778.html> > and look at the FAQs linked in that post for hints. In particular, do > not do DNS verification of RCPT TO domains during SMTP from Mailman. > > -- > Mark Sapiro <[email protected]> The highway is for gamblers, > San Francisco Bay Area, California better use your sense - B. Dylan > ------------------------------------------------------ Mailman-Users mailing list [email protected] http://mail.python.org/mailman/listinfo/mailman-users Mailman FAQ: http://wiki.list.org/x/AgA3 Security Policy: http://wiki.list.org/x/QIA9 Searchable Archives: http://www.mail-archive.com/mailman-users%40python.org/ Unsubscribe: http://mail.python.org/mailman/options/mailman-users/archive%40jab.org
