Hi Trying to avoid my IP being grey/blacklisted (mainly with microsoft domains: hotmail/outlook/live.com), I've put the following option in my postfix main.cf default_destination_rate_delay = 10s This is working great, and every other mail sent to the same domain gets delayed for 10s by postfix. This is what I need for not being rate limited by microsoft But mailqueue started to get increased and it's because with this option active, only one of the eight amavis daemons I have up and ready are used to process mail. Only one avavis process cannot cope with the normal traffic in my server. As soon as I comment out the option and restart postfix, mail system starts to use 8 amavis process again. I've tried with "1s" instead of 10s, with no difference. Only one simultaneous amavis process is used when rate delay is active What am I missing that is making postfix ignore amavis settings when I activate rate delay? BTW, this is my amavis configuration for increasing process: grep servers /etc/amavis/conf.d/51-user-customised $max_servers = 8; grep amavis /etc/postfix/master.cf amavis unix - - - - 8 smtp Thank you!