On Mon, 3 Jun 2013, Petros <Petros.Listig@fdrive.com.au> 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. 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. Also note that it can be over-ridden by master.cf and in the case of smtpd it probably is.
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? EC2 should be fast enough. How many users are on the list? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/