On Wed, May 26, 2010 at 11:10 AM, Wietse Venema <wie...@porcupine.org> wrote: > Robert Lopez: >> This college has a contract with Rave Messaging to deliver high volume >> (ex campus emergency) communications via many vectors including email. >> >> In their requirements document, in the portion on email, they write: >> >> "IMPORTANT NOTE: When an emergency alert is sent by your institution, >> Rave will open multiple SMTP connections and attempt to send a large >> number of emails in a short period of time. Please ensure that there >> are no throttling or spam rules that would slow or prevent the >> delivery of these emails from Rave." > > If the system opens an insane number of SMTP connections to the > same SMTP server, then that will definitely be a problem. > > Postfix enforces concurrency controls when it sends out mail, to > avoid such problems. > >> "reject_unauth_pipelining >> Reject the request when the client sends SMTP commands ahead of >> time WHERE IT IS NOT ALLOWED, or when the client sends SMTP >> commands ahead of time WITHOUT KNOWING THAT POSTFIX ACTUALLY >> SUPPORTS ESMTP COMMAND PIPELINING. > > a) the system sends commands together where it is not allowed by > RFC 2920, even after prior negotiation, or b) the system sends > commands together without prior negotiation as per RFC 2920. > > Wietse >
Thank you. Prior to reading RFC 2920 I was assuming that pipelining was a bad thing done by spammers. I never comprehended it could be a good thing if managed by both ends correctly. At a web meeting today I was told they will use 40 concurrent connections. With the default max connection limit (given no other server resource limits) I suppose that is not blasting an insane number of SMTP connections. Would this situation be better if I moved reject_unauth_pipelining from smtpd_client_restrictions to smtpd_data_restrictions, taking it out completely, or leaving it as it is? -- Robert Lopez Unix Systems Administrator Central New Mexico Community College (CNM) 525 Buena Vista SE Albuquerque, New Mexico 87106
