Hi Russell, thanks for the answer.
From: "Russell Coker" <[email protected]> > On Mon, 3 Jun 2013, Petros <[email protected]> wrote: >> If I send many e-mails at the same time, I have a high number of >> re-delivery attempts because initially connections time out. >> >> I am playing with some parameters in main.cf but haven't been very >> successful yet. >> >> At the moment my main.cf says: >> >> smtp_destination_rate_delay = 120s >> smtp_destination_concurrency_limit = 1 >> initial_destination_concurrency = 1 >> default_process_limit = 5 > > http://www.postfix.org/postconf.5.html#smtp_destination_concurrency_limit > > smtp_destination_concurrency_limit is per recipient. So it will reduce the > number of connections when sending to gmail and yahoo but not much else. Yes. I would have liked one that would limit the number of outgoing SMTP connection globally but I could not find a parameter for it. > From the same URL the default_process_limit is the number of processes that > the master process spawns, this will affect the DEFAULT for inbound > connections but not much else. Yep, seems so. Although it could be used to delay transfer from mailman to postfix, I thought. At the moment the recipient list is limited to 50 per connection (so mailman divides the list in chunks when sending mail). If I send it to 1 (default_process_limit = 1) it would restrict the number of recipients to 50 at the time, I think. I just don't know when mailman is sending the next chunk then (after one connection is closed?) >> BTW: The server is in the Amazon EC2 cloud but I don't think it >> matters. Still, if I try a telnet on port 25, the connection opens >> faster from my office (ADSL) than from the Amazon VM. > > Is there a reverse DNS issue? Well, the reverse lookup resolves to ec2-...us-west-2.compute.amazonaws.com not to the used sender address because it is a dynamic address. At the moment I update it on internal DNS (I don't control the external) so if mail arrives at the company server it can redirect list mail to the Amazon computer. > EC2 should be fast enough. How many users are on the list? Ca. 500 users. It is an announcement lists only. At the moment, I still have 56 mails left, after ca. 3 hours. It took ca. an hour to deliver the first 250. The main reason is "Connection time out", according to mailq. The mail itself is a PDF with less than one 1 Mbyte. I am surprised by the slowness. I wonder whether Amazon is throttling SMTP traffic. We have our mail server inhouse, and having the list server inhouse is clogging the ADSL connection. So I try Amazon, I thought. We do not own rack space otherwise I would have done it in a datacentre. Regards Peter _______________________________________________ luv-main mailing list [email protected] http://lists.luv.asn.au/listinfo/luv-main
