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Resolved Postfix smtp delay

ErwanG

Regular Pleskian
Hello,

I've a problem with a server with Postfix.
Emails (smtp) are refused by an operator because there is too many mail sent in a few moment.

With Qmail, we make this config :
1) we create file concurrencyremote
# vi /var/qmail/control/concurrencyremote
with the value 3
2) we restart Qmail and it's ok

With Postfix, we make that :
1) we modify the file /etc/postfix/main.cf
default_destination_concurrency_limit = 3
2) In /etc/postfix/transport :
wanadoo.com slow ;
wanadoo.fr slow ;
orange.fr slow ;
orange.com slow ;
laposte.net slow ;
.wanadoo.com slow ;
.wanadoo.fr slow ;
.orange.fr slow ;
.orange.com slow ;
3) After :
#postmap /etc/postfix/transport
4) In /etc/postfix/master.cf :
slow unix - - n - 5 smtp -o syslog_name=postfix-slow -o smtp_destination_concurrency_limit=3 -o slow_destination_rate_delay=1
5) In /etc/postfix/main.cf :
slow_destination_recipient_limit = 20
slow_destination_concurrency_limit = 3
And we modify :
transport_maps = hash:/var/spool/postfix/plesk/transport, hash:/etc/postfix/transport
6) At the end :
# /etc/init.d/postfix reload

But it doesn't work. Operator "Orange" refused emails.
In maillog, we have :
dsn=4.3.0, status=deferred (mail transport unavailable)

Help !!
Thank you
 
What worked for me (on a non Plek host but I had the same issues) :

In main.cf, add unit for time :
slow_destination_rate_delay = 1s

In master.cf, remove slow_destination_rate_delay as it doesn't seem necessary (!?)
 
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