Re: Used to run my own mail server 6 or 7 years ago, but stopped
There are also plenty of config options in Postfix to control how the smtp daemon will behave. For example, maximum simultaneous connections per client, maximum connection rate per client, and also options to slow down the smtp chat (effectively tarpitting) based on the number of errors.
Some options in the config can be set to be 'stress dependent' too, so you set a limit to the number of SMTP processes you want to run (eg 50) and if that's reached, then the stress config is used.