Victor Duchovni wrote:
On Wed, Mar 09, 2011 at 10:21:44PM +0000, Tim wrote:
Victor Duchovni wrote:
On Wed, Mar 09, 2011 at 09:40:26PM +0000, Tim wrote:
What happens is that Postfix receives the message from the sender, queues
it, then immediately connects to *all* of the destination servers
simultaneously and starts sending the message to them. This completely
saturates the upstream Internet link, so each destination server sees a
gradual trickle of data, and virtually all of them time-out while
receiving data.
On a server with limited network capacity set a small process limit for
the "smtp unix ... smtp" delivery agent entry in master.cf.
http://www.postfix.org/master.5.html
Thanks.
Not sure I fully understand what effect that will have, but I've set the
process limit to 2.
Will that restrict the number of outgoing connections to 2? I'm confused.
Each delivery agent delivers one message at a time. With two delivery
agents there are at most two parallel deliveries. The default process
limit is 100. I would first try 10 or 20, before taking it all the way
down to 2. Such a small process limit can create severe congestion...
Ah, right. I think I understand now - thank you very much.
I will try a value of 20 first, and see what happens.
Thanks very much for your help.
