In postfix settings: smtpd_delay_reject seems a bit too slow. "Temporarily unavailable try again later." Where is the delay time defined? I would like it not to be longer than 3min.
I do not understand your question. See postfix doku for the options: https://www.postfix.org/postconf.5.html smtpd_delay_reject = yes is no time delay! It causes postfix to wait until the client sends the "RCPT TO" command before evaluating other restrictions and send the client a deny. This option is useful a) as a bugfix for broken clients, b) to see the wanted recipient of a denied message in the logfile. It causes a delay in the fraction of a second. It has nothing to do with the rest of your post. [edit] Reading your post again, you seem to look for the queue lifetimes. See the following for your current settings and read the dokumentation for what they do. If questions remain, ask Code: postconf|egrep "queue_run_delay|minimal_backoff_time|maximal_backoff_time|maximal_queue_lifetime"
Changing the delay time wouldn't change anything if you are the receiver and the sender gets this message. If that's the case you'll have to whitelist the sending system. If you are the sender and you get this message you may want to tweak backoff_time parameters. For reference: https://www.postfix.org/postconf.5.html#minimal_backoff_time
Thx 4 the tip Mich. I'll have to take a look at that doc since I don't have Greylisting enabled. In my humble opinion Greylisting and every type of delays should stay under a minute or two since the Spammers surely know how to avoid them.
Well that highly depends of the intrest of the spammer and his coding skills; I think there are a lot of cases where the spammers are way to lazy to midigate greylisting, so sure it helps!
