2016-07-29 21:41:25 UTC
relay and having some difficulty reaching some destinations due to
apparent problems with too many concurrent connections.
I'm trying to solve the problem where this relay receives mail from
one of the corporate servers where it is scanned on this relay server
before being sent on to user's mailboxes.
279628D68138D 33026 Fri Jul 29 17:09:21 ***@example.com
(host mailstore1.secureserver.net[126.96.36.199] refused to talk to
me: 421 p3plibsmtp01-06.prod.phx3.secureserver.net bizsmtp Connection
refused, too many sessions from 188.8.131.52. Please lower the
number of concurrent sessions. IB007 <http://x.co/rlbounce>)
I've tried to configure destination concurrency, but I must not be
doing it correctly. Can someone review my changes and let me know what
I'm doing wrong?
transport_maps = regexp:/etc/postfix/transport_limit
default_destination_concurrency_limit = 10
turtle_initial_destination_concurrency = 1
turtle_destination_concurrency_limit = 1
turtle_destination_rate_delay = 4s
turtle_destination_recipient_limit = 2
I realize that by setting initial_destination_concurrency to 1 it's on
a per-domain basis, which is what I believe I need.
I've read the TUNING_README (a number of times over the years), but
perhaps it was written before sites like secureserver.net have chosen
to restrict inbound connections, not because of load, but instead for
Can someone make some recommendations on what the suggested/acceptible
number of concurrent connections to sites like secureserver.net and
others would be?