Thanks for your response Victor. So, if i want max 3 connections (to domain.tld), is this configuration could work (?) :
# in main.cf : transport_maps = hash:/etc/postfix/transport slow_destination_concurrency_limit=3 # in /etc/postfix/transport domain.tld slow: # in master.cf : slow unix - - n - 5 smtp thanks, -- Myrdhin,
