We are seeing: "has exceeded the maximum number of connections" in our
logs for domains associated with outlook.com. We have a transport
named "outlook:" in transport.regexp as follows:
# outlook.com domains
#
/@outlook(\.[a-z]{2,3}){1,2}$/ outlook:
/@hotmail(\.[a-z]{2,3}){1,2}$/ outlook:
/@live(\.[a-z]{2,3}){1,2}$/ outlook:
/@msn\.com$/ outlook:
main.cf is configured as follows:
outlook_destination_concurrency_limit = 6
outlook_destination_concurrency_failed_cohort_limit = 100
outlook_destination_concurrency_positive_feedback = 1/3
outlook_destination_concurrency_negative_feedback = 1/8
This transport is configured as follows in master.cf:
outlook unix - - n - 6 smtp
-o syslog_name=outlook
We can control the number of "has exceeded the maximum number of
connections" messages we see by limiting the number of processes in
master.cf.
We would like to use Per-Destination Connection Caching to increase
our throughput for "outlook:". Our mail server does not specify
"relayhost =" in main.cf. Is it possible to associate per-destination
caching with the "outlook:" transport? If not, what is the best
alternative?
If the answer is something like the following in main.cf:
smtp_connection_cache_destinations = hotmail.com, hotmail.es,
hotmail.co.uk, outlook.com, outlook.es, live.com, msn.com
should we try to include All the domains associated with "outlook:" so
even small volume domains are not counted as connections by
outlook.com servers? If this is the case, should/can we point
"smtp_connection_cache_destinations =" to a regexp file?
We are not seeing "conn_use=" in our logs. Is it true that Postfix
will not log "conn_use=" for current releases? We are running
postfix.x86_64 2:3.3.1-12.el8.
Thanks, Greg
www.RayStedman.org
